


VOICHIS 

4ACKALk 




Class 
Book 



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COPYRIGHT DEPOSIT. 



UP-TO-DATE 



Air-Brake Catechism 



THE ONLY PRACTICAL AND COMPLETE WORK PUBLISHED, 
TREATING ON THE EQUIPMENT MANUFACTURED BY THE 
WESTINGHOUSE AIR BRAKE COMPANY, INCLUDING THE ET 
LOCOMOTIVE BRAKE EQUIPMENT ; THE K (qUICK-SERVICE) 
TRIPLE VALVE FOR FREIGHT SERVICE; THE TYPE L HIGH- 
SPEED TRIPLE valve; the P C PASSENGER-BRAKE EQUIP- 
MENT, AND THE CROSS COMPOUND PUMP. THE OPERATION OF 
ALL PARTS OF THE APPARATUS IS EXPLAINED IN DETAIL, 
AND A PRACTICAL WAY OF FINDING THEIR PECULIARITIES 
AND DEFECTS WITH A PROPER REMEDY IS GIVEN. 

2,500 QUESTIONS WITH THEIR ANSWERS 

are included. These are intended as examination questions 

for engineers and firemen, and all other railroad men 

preparing to pass an examination on the subject of 

air brakes. This book has been endorsed and used 

by air-brake instructors and examiners on 

nearly every railroad in the United States 

By ROBERT H. BLACKALL 




Fully Illustrated by Detail Engravings and Colored Plates 

TWENTY-SIXTH EDITION 

ENTIRELY REVISED TO DATE 



NEW YORK 

THE NORMAN W. HENLEY PUBLISHING CO. 
132 Nassau Street 

1914 



ss 






Copyrighted 1914. 1911. 1908 and 1907 
By 
THE NORMAN W. HENLEY PUBLISHING COMPANY 



Copyrighted 1903, 1900 and 1898 

By 
NORMAN W. HENLEY & CO. 




Composition, Dectrotyping and 
Presswork by Macgowan & 
Slipper, New York City 



AUG -8 1914 

' CI,A376913 



:k- 



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ifjitrattan 






THIS BOOK 


IS 


LOVINGLY 
TO MY 


DEDICATI 


:d 


FATHER 


AND MOTHER 





Preface to the Twenty -Sixth Edition 

THE fact that this is the twenty-sixth edition of this 
book indicates that there is an urgent need for a 
book of this nature written on the question and answer 
plan, by means of which it is possible to readily locate the 
particular point upon which information is desired. 

The air-brake art has almost completely changed in the 
last seven years, hence the necessity for an entirely new 
edition. 

The changed conditions of service which now pre- 
vail, and which consist of longer trains, cars of heavier 
capacity and locomotives with power and weight com- 
mensurate with their increased duties, have made impera- 
tive some radical changes in the air brake. The original 
brake was designed with the idea in mind that the maxi- 
mum length of train would be fifty cars, and the capacity 
of these cars 60,000 pounds. A large percentage of the 
cars of to-day have a capacity of 100,000 pounds, the 
number of cars in a train is often 100 and the hauling 
power of the locomotive has kept pace. The result of 
these changes has been that the apparatus which has 
been in use for so many years is not adequate to handle, 
with the desired efficiency, the long and heavy trains of 
to-day. 

Passenger cars and engines have more than doubled 
in weight and it has also been necessary to re-design this 
equipment that stops may be possible within desirable and 
Practical limits. 

To meet these changed conditions in freight service 



PREFACE 

the Westinghouse Air Brake Company has developed new 
engine and car equipment by the use of which even 
better results are obtained with the long and heavy trains 
than could be obtained with the older equipment and 
shorter trains. 

They have also developed a passenger car equipment 
which, aside from the improvements in the way of flex- 
ibility and other new features, will permit of this heavier 
equipment being brought to a stop in about the same 
distance as was accomplished with the older form of high- 
speed brake and the lighter equipment in general use dur- 
ing the previous ten years. 

The author takes this opportunity of thanking those in- 
terested in the air-brake art for the generous and cordial 
support which former editions of this book have received. 

July, 1914.. ROBERT H. BLACKALL. 



TABLE OF CONTENTS 



CHAPTER I. PAGE 

Beginnings of the Air Brake 17-20 

CHAPTER II. 

The Westinghouse Triple Valves — The Plain Triple 
Valve — Functions of the Triple Valve in the Opera- 
tion of the Brake — Quick-Action Triple Valve — Pe- 
culiarities and Troubles of the Quick-Action Triple 
Valve— The Type "K" Triple Valve— The Type *'L" 
Triple Valve 21-78 

CHAPTER III. 

Westinghouse Freight Equipment — Piston Travel — The 
American Automatic Brake-Slack Adjuster and 
Piston-Travel Regulator — Pressure Retaining Valves 79-112 

CHAPTER IV. 

Westinghouse Air Pumps — Nine and One-Half Inch 
Pumi) — Nine and One-Half Inch Pump, Peculiari- 
ties, Troubles, Care— Westinghouse "Right and 
Left-Hand" Nine and One-Half Inch Pump— West- 
inghouse Eleven Inch Pump — The Eight and One- 
Half Inch Cross-Compound Pump — The Present 
Standard ( SF-4) Pump Governor 113-145 

CHAPTER V. 

Main Reservoir — G-6 Engineer's Brake Valve — Westing- 
house Slide- Valve Feed Valve — The Equalizing Res- 
ervoir, or Little Drum, or Cavity D — Peculiarities 
and Troubles of the G-6 Brake Valve — Duplex Main- 
Reservoir Regulation, as Used with all Standard 
Westinghouse Equipments 146-177 

CHAPTER VI. 

Westinghouse Old-Style High-Speed Brakes — Double 
Pressure Control Equipment or Schedule LT — West- 
inghouse Old- Style Combined Automatic and 
Straight Air-Brake Equipment for Engines and 
Tenders— Straight Air-Brake Valve 178-205 

CHAPTER VII. 

The Westinghouse No. 6 ET Locomotive Brake Equip- 
ment — Brake Valves for ET Equipment — H-6 Auto- 
matic Brake Valve — The S-6 Independent Brake 
Valve — The No. 6 Distributing Valve — Independent 
Application — Automatic Operation — The Quick-Ac- 
tion Cylinder Cap — The Use of the Safety Valve — 



TABLE OF CONTEXTS 

PAGE 
Feed Valves— The B-6 Feed Valve— The C-6 Reduc- 
iug Valve — The Pump Governor — Defects of ET 
Equipment — Principal Differences Between the No. 
5 and No. 6 ET Equipments 206-260 

CHAPTER VIII. 

Air- Signal System — Peculiarities and Troubles of the 

Signal System 261-273 

CHAPTER IX. 

Braking, Power and Leverage — Sizes oi Cylinders to be 
Used on Cars and Tenders — American Brake Lever- 
age — Cam Brake — Air Hose — Air-Brake and Signal- 
Hose Specifications — Bursting Test — Friction Test 
—Stretching Test 274-298 

CHAPTER X. 

The Sweeney Compressor — The Water Brake — Water 
Brake on Simple Engine — The Baldwin Water 
Brake on Baldwin Compounds — Air-Brake Record- 
ing Gages — Lubricants 299-309 

CHAPTER XL 
Train Inspection — Train Handling — Description of Tests 

—Piping 310-342 

CHAPTER XII. 

A Few Practical FormuUe and Rules for Air-Brake 

Inspectors 344-348 

CHAPTER XIII. 

The **PC'* Passenger Brake Equipment — Object of Equip- 
ment — Novel Features — Names of Parts — How 
Various Features Are Obtained — The No. 3-E Con- 
trol Valve — Control-Valve Portions — Duties of 
Each — Names of Parts — Parts and Their Connec- 
tions — Normal Position — Release Position, Charging 
Pressure Chamber and Reservoirs — Preliminary 
Service Position — Secondary Service Position — Ser- 
vice Position — Service Lap Position — Over-Reduc- 
tion Position — Over-Reduction Lap Position — Pre- 
liminary Release Position — Secondary Release Posi- 
tion — Graduated Release Position — Graduated Re- 
lease Lap Position — Direct Release Position — 
Emergency Position — Brake Cylinders — Handling of 
Brake Valve — Location of Exhaust Outlets — Treat- 
ment for Leaks at Exhaust Outlets — Lubrication of 
Control Valve — Common Exhaust Reservoir 349-404 

The Centrifugal Dirt Collector — Purpose — Location — 

Operation — Cleaning 405-406 



List of Illustrations 

OF 

WESTINGHOUSE AIR BRAKE AND SIGNAL EQUIPMENT 

Fig. 1. Old Style Plain Triple Valve, Release Position 23 

Fig. 2. Plain Triple Valve, Service Position 25 

Fig. 3. Plain Triple Valve, Lap Position 26 

Fig. 4. Plain Triple Valve, Emergency Position 30 

Fig. 4a. Colored Plate of Old Standard Quick-Action Triple 

Valve — Release and Chaurging Position. . . .facing 36 

Fig. 5. Quick-Action Triple Valve, Release Position 37 

Fig. 6. Quick-Action Triple Valve, Service Position 38 

Fig. 7. Quick- Action Triple Valve, Lap Position 39 

Fig. 8. Quick- Action Triple Valve, Emergency Position 42 

Fig. 9. Slide Valve Bushing 43 

Fig. 10. Slide Valve 43 

Fig. 11. K Triple Valve — Exterior View 54 

Fig. 12. K Triple Valve— Cross Section 55 

Fig. 13. K Triple Valve — Graduating Valve, Slide Valve, and 

Slide-Valve Seat 57 

Fig. 14. K Triple Valve— Full Release 58 

Fig. 15. K Triple Valve — Service Position 59 

Fig. 16. K Triple Valve — Service-Lap Position 60 

Fig. 17. K Triple Valve — Retarded Release Position 61 

Fig. 18. K Triple Valve — Emergency Position 62 

Fig. 19. Type L Triple Valve 64 

Fig. 20. Type L Triple Valve 65 

Fig. 21. Diagram of Type L Triple Valve — 

Release and Charging Position 66 

Fig. 22. Diagram of Type L Triple Valve— 

Quick-Service Position 67 

Fig. 23. Diagram of Type L Triple Valve— 

Service-Lap Position 68 

Fig. 24. Diagram of Type L Triple Valve— 

Full-Service Position 69 



LIST OF ILLUSTRATIONS. 

Fig. 25. Diagram of Type L Triple Valve — 

Release-Lap Position 70 

Fig. 26. Diagram of Type L Triple Valve — 

Emergency Position 71 

Fig. 27. Westinghouse Freight Equipment 80 

Fig. 28. Showing Application of American Brake Slack 

Adjuster to a Passenger Car Equipment 95 

Fig. 29. Sectional End View of American Automatic Brake- 
Slack Adjuster 97 

Fig. 30. Showing Proper Method of Drilling Brake Cylinders 
WTien L'sed with the American Automatic Brake- 
Slack Adjuster 100 

Fig. 31. Sectional View of Pressure-Retaining Valve 103 

Fig. 32. The Westinghouse Double-Pressure Retaining Valve 105 
Fig. 33. Retaining Valve Used with 12, 14, and 16-inch Brake 

Cylinders 110 

Fig. 34. *Tullman" Retaining Valve, L'sed on Vestibule Cars 110 
Fig. 35. Standard Retaining Valve Used with 6, 8 and 10-inch 

Brake Cylinders 110 

Fig. 36. Driver-Brake Retaining Valve Ill 

Fig. 36a. Colored Plate- Nine and One-Half-Inch Pump . . facing 113 

Fig. 37. Westinghouse 9i^-inch Air Pump 114 

Fig. 37a Westinghouse 9%-inch Air Pump il5- 

Fig. 38. Right and Left-Hand Pump 127 

Fig. 39. Eight and One-Half Cross-Compound Pump 130 

Fig. 40. Diagram of Cross-Compound Pump — 

Up Stroke High-Pres'5ure Side 132 

Fig. 41. Diagram of Cross-Compound Pump — 

Down Stroke, High-Pressure Side 133 

Fig. 42. Old Standard Pump Governor 140 

Fig. 43. Colored Plate— Present Standard SF-4) Pump Gov- 
ernor facing 143 

Fig. 44. Main Reservoir Drain Cock 149 

Fig. 4.5. D-S Engineer's Brake Valve — Release Position.... 151 

Fig. 46. G-6 Engineer's Brake Valve — Release Position 152 

Fig. 47. G-6 Engineer's Brake Valve — Running Position... 153 

Fig. 48. G-6 Engineer's Brake Valve — Plan View 154 

Fig. 49. Feed Valve — Section Through Supply Valve Piston 162 

Fig. 50. Feed Valve — Section Through Regulating Part 163 

Fig. 51. Rotary Valve of G-6 Brake Valve (top view) 164 



LIST OF TLLrSTRATlON'?;. 

Fig. 52. Bottom View of Rotary Valve of G-6 Brake Valve.. 164 

Fig. 53. The Little Drum, or Cavity D 167 

Fig. 54. Diagram of Westingliouse Duplex ]Main — Reservoir 

Regulation 175 

Fig. 55. Method of Drilling Brake Valve for Duplex Main — 

Reservoir Regulation 176 

Fig. 56. Method of Drilling Brake Valve for Duplex Main — 

Reservoir Regulation 176 

Fig. 57. Highspeed Automatic Reducing Valve 180 

Fig. fiTA. Diagrammatic Illustration of Old Style Westing- 
house High-Speed Brake Equipment 182 

Fig. 58. Section of High Speed Reducing Valve, Showing 

Position of Ports in Emergency Stop 184 

Fig. 59. Section of .High-Speed Reducing Valve, Showing 
Position of Ports with Cylinder Pressure 

Slightly Exceeding 60 Pounds 184 

Fig. 60. Section of High-Speed Reducing Valve, Showing 

Position of Ports in Release Position 184 

Fig. 61. Showing Location of High-Speed Automatic Reduc- 
ing Valve Under Car 186 

Fig. 62. Progress of Air Brake Efficiency as Shown by Com- 
parative Distances in Which Trains Are Stopped 188 
Fig. 62a. Diagrammatic Hlustration of Westinghouse Double- 
Pressure Control Apparatus or Schedule U 190 

Fig. 63. Old Style Safety Valve 192 

Fig. 64. New Style Safety Valve 192 

Fig. 64a. Combined Automatic and Straight Air Brake Equip- 
ment as Applied to Freight Engine and Tender 194 

Fig. 65. Double Check Valve 196 

Fig. 66. Straight-Air Brake Valve 199 

Fig. 67. Straight Air Brake Valve 199 

Fig. 68. Straight Air Brake Valve 200 

Fig. 69. Straight Air Brake Valve 200 

Fig. 70. Section Through Straight-Air Brake Valve 200 

Fig. 71. Colored Plate— Piping Diagram of No. 6 E T Equip- 
ment facing 207 

Fig. 72. The H-6 Automatic Brake Valve 212 

Fig. 73. Colored Plate— The H-6 Automatic Brake Valve 

facing 213 
Fig. 74. Brake Valves — Positions of Handles 214 



LIST OF ILLrsrRATIOXS. 

Fig. 75. H-6 Automatic Brake Valve 216 

Fig. 76. S-6 Independent Brake Valve 222 

Fig. 77. Colored Plate -Tiie S-6 Automatic Brake Valve 

facing 223 

Fig. 78. Interior Views of the S-6 Independent Brake Valve 224 

Fig. 78a. Distributing Valve in Released and Charging 

Position facing 228 

Fig. 79. Distributing Valve and Double Chamber Reservoir 229 

Fig. 80. Distributing Valve and Double Chamber Reservoir 229 

Fig. 81. Release Position — Automatic or Independent 230 

Fig. 82. Independent Application 231 

Fig. 83. Independent Lap 232 

Fig. 84. Automatic Service 233 

Fig. 85. Service Lap 234 

Fig. 86. Emergency 235 

Fig. 87. Emergency Lap 236 

Fig. 88. Independent Release When Brake Has Been Applied 

Automatically 237 

Fig, 89. Emergency ^Mien the Quick-Action Cap Is Used.. 238 

Fig. 90. Graduating Valve, Equalizing Slide Valve and 

Slide Valve Seat 239 

Fig. 91. Distributing Valve, Showing Connections 242 

Fig. 92. Quick-Action Cylinder Cap 248 

Fig. 93. B-6 Feed Valve 252 

Fig. 94. Single Equipment for Engine With Engines Not 

Equipped With Schedule E T 262 

Fig. 95. Location of Signal Apparatus on Coach 263 

Fig. 96. Air Strainer on Engine 264 

Fig. 97. Car Discharge Valve 265 

Fig. 9S. Westinghouse Signal Valve 266 

Fig. 99. Westinghouse Signal Reducing Valve 267 

Fig. 100. Signal Whistle 268 

Fig. 101. Lever of First Class 277 

Fig. 102. Lever of First Class Applied to Car Wheel 279 

Fig. 103. Lever of Second Class 280 

Fig. 104. Lever of Second Class, Applied to Car Wheel 281 

Fig. 105. Lever of Third Class 281 

Fig. 106. Lever of Third Class, Applied to Car Wheel 281 

Fig. 107. Hodge System of Leverage 283 

Fig. 108. Stevens System of Leverage 287 



LIST OF ILLUSTRATIONS. 

Fig. 109. Hodge System of Leverage 287 

Fig. 110. Leverage System for Tenders 287 

Fig. 111. American Driver — Brake Leverage 289 

Fig. 112. Sliowing Markings on Air-Hose 295 

Fig. 113. Method of Testing Hose 297 

Fig. 114. Water Brake on Simple Engine 301 

Fig. 115. Baldwin Water Brake for Compound Engines — 

Side View 303 

Fig. 116. Baldwin Water Brake for Compound Engines — 

Front View 304 

Fig. 117. Air-Brake Recording Gauge — Revolving Type 308 

Fig. 118. PC Passenger Brake Equipment, Cylinders Point- 
ing in Opposition Directions (Plate) . .opposite 349 
Fig. 119. PC Passenger Brake Equipment, Cylinders Point- 
ing in Same Direction (Plate) opposite 349 

Fig. 120. No. 3-E Control Valve, Side View 356 

Fig. 121. No. 3-E Control Valve, Front View 357 

Fig. 122. No. 3-E Control Valve, Showing Different Portions 

of the Valve 357 

Fig. 123. No. 3-E Control Valve, Outline 358 

Fig. 124. No. 3-E Control Valve, Outline 359 

Fig. 125. No. 3-E Control Valve, Actual Section 360 

Fig. 126. No. 3-E Control Valve, Actual Section 361 

Fig. 127. Equalizing Graduating Valve, Slide Valve, and 

Slide Valve Seat 362 

Fig. 128. Release Graduating Valve, Slide Valve, and Slide 

Valve Seat 363 

Fig. 129. Emergency Slide Valve and Slide Valve Seat 364 

Fig. 130. Diagram, Normal Position 366 

Fig. 131. Diagram, Release Position Charging Pressure 

Chamber and Reservoirs T 367 

Fig. 1.32. Diagram, Preliminary Service Position 370 

Fig. 133. Diagram, Secondary Service Position 371 

Fig. 134. Diagram, Service Position 373 

Fig. 1.35. Diagram, Service Lap Position 376 

Fig. 136. Diagram, Over-Reduction Position 378 

Fig. 137. Diagram, Over-Reduction Lap Position 380 

Fig. 138. Diagram, Prelimimary Release Position 382 

Fig. 139. Diagram, Secondary Release Position 383 

Fig. 140. Diagram, Graduate Release Position 385 



LIST OF ILLUSTRATIONS. 

Fig. 141. Diagram, Graduated Release Lap Position 387 

Fig. 142. Diagram, Direct Release, Charging Pressure Cham- 
ber Only 389 

Fig. 143. Diagram, Emergency Position, Quick-Action Valve 

Venting 391 

Fig. 144. Diagram, Emergency Position, Quick-Action Valve 

Closed 392 

Fig. 145. Brake Cylinder Used With the PC Equipment 395 

Fig. 146. Section Through Control Valve Reservoir Having 

Common Exhaust 402 

Fig. 147. Control Valve, Common Exhaust Reservoir, Side 

View 403 

Fig. 148. Control Valve With Common Exhaust Reservoir, 

Outline 404 

Fig. 149. Centrifugal Dirt Collector 40t) 



AIR-BRAKE CATECHISM 



CHAPTER I. 

BEGINNINGS OF THE AIR BRAKE 

Q. What is an air brake? 

A. A brake operated by compressed air. 

Q. What was the first form of air brake used? 

A. The straight air brake. 

Q. By whom and when was it invented? 

A. By George Westinghouse, in 1868. 

Q. What forms of brake did it supplant? 

A. The hand and the spring brakes. 

Q. What parts were necessary to operate the straight 
air brake? 

A. An air pnmp^ main reservoir, a valve called the three- 
way cock used to control the application and release of the 
brakes, a brake pipe, and brake cylinders. 

Q. What parts were on the engine? 

A. A main reservoir, pump, and engineer's valve. 

Q. What parts were on the car? 

A. The brake pipe and cylinder. 

Q. Where was the braking power stored with this 
system? 

A. In the main reservoir on the engine. 

Q. How were the brakes applied? 

A. By changing the position of the three-way cock on the 



18 Air-Beake Catechism 

engine so as to allow the main reservoir pressure to flow into 
the brake pipe. The brake pipe, connected directly with the 
brake cylinder, allowed air to pass into the cylinder, forcing 
the piston out and applying the brake. 

Q. Why was this brake unsatisfactory? 

A. For several reasons. First, the tendency of the brakes 
was to apply first at the head end of the train. If they were 
applied suddenly the slack running ahead would cause severe 
shocks and damage. Second, if a hose burst in the train, the 
brakes could not be set with air, as it would pass out through 
the burst hose to the atmosphere. Third, on a long train the 
main-reservoir pressure would equalize with that in the brake 
pipe and brake cylinders at a low pressure on account of the 
large space to be filled; before the brakes were fully set the 
engineer would have to allow the pump to compress air into 
the brake pipe, and brake cylinders, and before maximum 
braking power was obtained the train would be stopped. 
Fourth, the effect of friction on the flow of air from the main 
reservoir through a long train made this brake apply much 
slower. 

Q. What was the next form after the straight air 
brake? 

A. The plain automatic. 

Q. By whom and when was it invented? 

A. By George Westinghouse, in 18T3. 

Q. What brake followed the plain-automatic brake? 

A. The quick-action brake, which almost immediately su- 
perseded the plain-automatic brake in passenger service, and 
did very quickly in freight service. With this improved ap- 
paratus the brake on the last of a fifty-car train could, if so 
desired, be applied in two and one-half seconds from the move- 
ment of the brake valve handle on the eno^ine. 



Beginxixgs of the Air Brake 19 

Q. Is the quick-action brake still in use? 

A. Yes; all passenger and freight cars are now equipped 
with this brake, but at present a modified form is in general 
use in passenger, mail and express service. The modified 
form is known as the high-speed brake, the operation of which 
is described in another part of this book. 

Q. Have any modifications in the general equipment 
of the quick-action brake been made in freight service? 

A. Not in the car equipment itself aside from the addition 
of the retaining valve, and the modification of certain details 
to render the apparatus more effective for conditions now 
existing. 

Q. What changes have been made in the engine equip- 
ment? 

A. The engine equipment has been gradually developed 
to meet modern conditions. The modifications include double- 
pressure control apparatus, commonly known as schedule IT, 
the duplex method of main reservoir regulation, and the com- 
bined automatic and straight-air brake, all of which are il- 
lustrated and described in detail in other parts of this book. 
Within the past three years, a complete and new engine, 
freight and passenger car equipment has been developed by 
the Westinghouse company. 

Q. What else has been developed along wth the air- 
brake apparatus used in passenger service? 

A. The air signal system. * 

Q. What gains over the hand brake are made with the 
air brake? 

A. With a train of fifty modern equipped air-brake cars, 
a full and harder set brake is obtained on the entire train 
more quickly than a hand brake can be set on one car. Since 
trains handled on heavy grades have to be slowed down for 
the purpose of recharging, by this means the wheels are given 



20 AiR-BrAKE C'ATECHTSil 

a chance to cool. Witli the liand brakes used on heavy grades, 
the shoes grind against the wheels down nearly, or quite all 
the grade so that often the train is wrecked because the 
wheels are heated to so high a temperature that they break, 
especially where only part of the brakes are used, or where 
the efficiency varies greatly. Air brakes give us an increased 
speed of trains with greater safety. 



CHAPTEE II. 

THE WESTINGHOUSE TRIPLE VALVES 

Q. Where was the difference in the car equipment be- 
tween the straight-air and automatic brake made? 

A. Besides the brake pipe and brake cylinder, a plain triple 
and an auxiliary reservoir were added to the car. 

Q. With the cars equipped with the automatic brake, 
what gain was made over the straight-air brake? 

A. (1) The necessary braking power for each car^ regard- 
less of the length of the train^ was stored in the auxiliary 
reservoir under that car, so that the brakes could be fully set 
very quickly^ as compared with the action of the straight-air 
brake. (2) If the train broke in two or a hose burst, the 
triples would automatically apply the brakes; whereas with 
the straight-air the brakes could not be applied. 

Q. What was the essential feature of the automatic 
brake? 

A. The plain triple valve. 

Q. Where was it located? 

A. On the car, at the junction of the brake pipe, auxiliary 
reservoir, and brake cylinder. 

Q. Did the pump and three-way cock remain on the 
engine? 

A. Yes ; this was left for later development. 

THE PLAIN TEIPLE VALVE. 

Q. In the study of the triple valve what is the main 
thing to be borne in mind in order to understand its oper- 



22 Aie-Beake Catechis:^! 

ation and its probable action under the many and varied 
conditions which are encountered in actual service? 

A. In the study of the triple valve^ as well as almost any 
other i^art of the air-brake or air-signal apparatus, a clearer 
understanding will result if one starts at a problem by first 
asking himself the question^ A^iich is the greater or controll- 
ing pressure acting on the part under consideration? With 
this point thoroughly understood the resultant action of the 
parts in question can be readily traced ; for instance, if a brake 
is applied, and there is a leak in the auxiliary reservoir, we 
know that this will have the effect of lowering the pressure on 
one side of the triple piston. We then know that the tendency 
will be for the piston to move away from the greater brake 
j^ipe pressure, and, as will be explained later, this effect will 
cause the release of the brake in question. 

Q. Name the different parts of the plain triple valve, 
Figs. 1 to 4. 

A. 13 and 15 are the cut-out cock and the handle; 8, the 
graduating post; 9, the graduating spring; m and n are feed 
ports ; 5 is the triple j^iston ; 6, the slide valve ; 7 is the grad- 
uating valve which works inside the slide valve; 12, a piston- 
packing ring; 18, slide-valve spring; Y, the port leading to 
the auxiliary reservoir; X leads to brake cylinder; IF leads 
to brake-piiDC pressure. 

Q. For what are valve 13 and handle 15 used? 

A. They permit the triple to be used with the straight air- 
brake, automatic brake, or cut out entirely, as illustrated by 
the cut (Fig. 1). 

Q. What three positions has the handle 15 (Fig. 1)? 

A. As shown in the cut, by the different positions of the 
handle: so that the triple would be cut in, as it is with the 
handle 15 at right angles to the triple; pointing straight down, 
in which case, air coming in at ^Y from the brake pipe would 



Plain Triple Valve 



23 



go through port e of the plugcock 13 and out into the brake 
cylinder through Z; or the handle could stand at an angle of 
45°, in which position ports /, a and d would all be blanked. 
In the first position the triple is cut in for automatic, in 




Fig. 1.— Old Style Plain Triple Valve, Release Positiox. 



the second for straight air, and in the third the triple is cut 
out entirely. 

Q. Can the modern plain triple now sent out be cut 
into straight air? 

A. Ifo. 



24 Air-Brake Catechism 

Q. Why not? 

A. Because, as shown in Figs. 2, 3 and 4, the handle 15 
and plug 13 are no longer used. The cut-out cock is now 
placed in the crossover pipe. 

Q. Why was it necessary to have it so arranged that it 
could be cut in as straight air? 

A. When the brakes were graduall}^ being changed from 
straight air to automatic^ it sometimes happened that only a 
few cars in the train had the triple applied. In this case the 
handle 15 was turned so as to cut the car into straight air 
to be used with the other straight-air cars. 

Q. Of what use are 8 and 9 (Fig. 1)? 

A. In applying the brakes^ when piston 5 moves out and 
touches the stem 8, held by the graduating spring 9, (Fig. 1), 
the piston is stopped^ if a gradual reduction is being made 
in the brake-pipe^ when the piston has drawn the slide valve 
down far enough to make a port connection between the au- 
xiliary and cylinder. 

Q. If a quick reduction is being made in the brake- 
pipe, will the spring 9 stop the triple piston? 

A. No; a quick reduction causes the triple piston 5 to 
move down quickly^ and the sudden impact compresses the 
spring 9^ allowing the piston 5 to move down until it strikes 
gasket 11, to what is known as emergency position. 

Q. 5 (Fig. 1) is called the triple piston. How is it 
actuated? ' 

A. Brake-pipe pressure is on the lower side of the piston 
and auxiliary pressure on the upper or slide-valve side. 
It is by changing these pressures that the piston is moved. 

Q. What are the duties of the piston as it moves? 

A. To open and close tlie feed ports m and n (Fig. 1) 
through which the brake-pipe pressure flows into the auxil- 



Plain Triple Valve 



25 



iary reservior, to move the graduating valve 7 and the slide 
valve 6. 

Q. What is the duty of the graduating valve 7 
(Fig. 1)? 



y 1/2 P'P^ tA^ 

BRAKE CYlIn'DER 



V 2 PIPE TAP 

TO AUXILIARY RESERVOIR 

Y 




1/2 PIPE TA^ 
TO TRAIN LINS 
W 



Fig. 2.— Plain Triple Valve, Service Position. 

A, It is the small valve inside the slide valve, and its 
duty as it is moved downward and upward by the triple 
piston is to open and close the port p through which, in the 



26 



Air-Brake Catechism 



service application, auxiliary-reservoir pressure flows to the 
brake cylinder. 

Q. Does the graduating valve move every time the 
triple piston moves? 



1/2 PIPE TAP kfit 
TO AUXILIARY RESERVOIR 
Y 




Fig. 3.— Plain Triple Valve,' Lap Position. 

A. Yes. because it is fastened to the stem of the piston by 
a pin which passes through both the graduating valve and 
the stem of the triple piston. The pin is represented by 



Plain Triple Valve 27 

the dotted lines running through the lower end of the 
graduating valve at right angles to it. 

Q. Could we get along without the graduating valve? 

A. Yes, but the sensitiveness of the triple would be de- 
stroyed. 

Q. How does the graduating valve make the triple 
sensitive? 

A. A reduction of brake-pipe pressure causes the triple to 
assume service position, and after the auxiliary pressure has 
expanded to a trifle below that in the brake-pipe, piston 5 
(Fig. 3), moves up and closes the graduating valve on its 
seat. Brake-pipe pressure had simply to overcome the fric- 
tion on the triple piston-packing ring to do this, but had we 
no graduating valve the brake-pipe pressure would have had 
to be strong enough to overcome the additional friction of 
the slide valve to move it back far enough to close port p. 
When wishing to apply brakes harder, a heavier reduction 
would be necessary to again move the slide valve to service 
position. By the use of the graduating valve, the slide valve 
is moved to service position with the first reduction, where 
it remains until the brake is released or in case the emergency 
is used. 

Q. What are the duties of the slide valve? 

A. In the plain triple, when moved by the triple piston, 
it serves to make a connection between the auxiliary-reservoir 
and the brake cylinder or between the brake cylinder and the 
atmosphere. 

Q. Does the slide valve move every time the piston 
moves? 

A. No; the slide valve will not move when the piston 
starts down until it has moved far enough for the lug just 
above 18 (Fig. 1) to strike the valve. Also, if the piston 
is down full stroke; when it starts back the slide valve will 



28 Aie-Brakz Catechism: 

not moTe until the piston has gone back far enough to seat 
the graduating valve. 

Q. Of what use is the spring 18, Fig. 1? 

A. Its duty is to hold the slide valve on its seat and to 
prevent dirt from collecting there when there is no auxiliary- 
reservoir pressure to hold the valve on its seat, as when the 
car is '^"dry/'^ 

Q. What is the difference in the four triple valves 
shown in Figs. 1, 2, 3, and 4. 

A. Tiiey are all plain triple valves, but the one showing 
release position is the older type which could be cut into 
straight air. The other three represent the modern valve 
which is cut out or in by means of a cutout cock placed in the 
cross-over pipe between the drain cup and triple valve. 

FUXCTIOXS OF THE TKIPLE VALVE IX THE 
OPEEATIOX OF THE BEAKE. 

Q. Why is this valve called the triple valve? 

A. Because it automatically does three thiQgs : charges the 
auxilian-reservoir, applies the brake, and releases it. 

Q. If an engine couples to a car that is not charged, 
how does the triple charge the auxiliary reservoir on the 
car when the hose is coupled and the angle cocks turned 
so as to allow the compressed air to flow into the brake- 
pipe on this car from the engine? 

A. A cross-over pipe from the brake-pipe couples to the 
triple at W (Fig. 1.) The pressure from the brake-pipe passes 
into the triple at W, through port c as indicated by the arrow 
iuto cavitv' B; thence through the feed ports m and n into the 
chamber where the slide valve moves and out into the auxil- 
iary-reservoir at Y. 



Functions of the Triple Valve 29 

Q. How long does the air continue to flow into the 
auxiliary reservoir? 

A. Just as long as the brake-pipe pressure is greater than 
that in the auxiliar}^^ that is, until the pressures are equal on 
the two sides of the triple piston 5. 

Q. How are the two sides of the piston referred to? 

A. The lower sicle^ having pressure on it, is called the 
brake-pipe side of the piston, and the upper side, having aux- 
ilary-reservoir pressure on it, the auxiliary or slide-valve 
side. 

Q. What is necessary to cause piston 5 (Fig. 1) to 
move from release position? 

A. Any reduction of brake-pipe pressure; a break in the 
hose ; the use of his valve bv the eno^ineer to make a brake- 
pipe reduction. 

Q. If a reduction of brake-pipe pressure is made, how 
does the triple respond? 

A. Auxiliary-reservoir pressure now being greater forces 
the triple piston down. 

Q. What two things does the piston do when it starts 
to move down? 

A. It closes the feed grooves m and n and moves the grad- 
uating valve from its seat. 

Q. Does the slide valve move as soon as the piston? 

A. Xo, not until the lug above 18 (Fig. 1) is drawn down 
far enough to rest against the slide valve. 

Q. What does the slide valve do as soon as the lug 
strikes and moves it down? 

A. It first closes the exhaust port g which in release posi- 
tion connected tlie brake cylinder with the atmosphere through 
X, (1, e, f, g, li and l\ 



30 



Air-Brake Catechism 



Q. How far down does the triple piston travel? 

A. Until the projecting stem of the piston strikes the stem 
8 held by the graduating spring 9 (Fig. 2). 



X 1/4 PIPE TAP 

BRAKE CYLINDER 



1/2 PIPE TAP 
TO AUXILIARY RESERVOIR 

Y 




Vi PIPE TAP 
TO TRAIN UNt;^ 

w 



I^iG. 4. — Plain Triple Valve, Emergency Position. 

Q. When these stems touch, how does the slide valve 
stand? 

A. Port p of tlie slide valve is in front of port /, and. as 
the graduating valve was pulled from its seat when the pis- 



Functions of the Triple Valve 31 

ton first moved^ the auxiliary-reservoir pressure is now free 
to pass into the slide valve through port l^ called the service or 
graduating port, which leads into port p. The air passes 
throught ports /, p, p, f, f, and out throught X to the brake 
cylinder. 

Q. How long does the graduating valve remain off its 
seat so as to allow auxiliary reservoir pressure to flow to 
the brake cylinder? 

A. We reduced the brake-pipe pressure to allow the greater 
auxiliary-reservoir pressure to move the piston down and open 
the service or graduating port p between the auxiliary and 
cylinder. Just as long as the auxiliary pressure is greater, the 
piston will stay down and the graduating valve remain un- 
seated. As the auxiliary pressure expands into the brake 
cylinder it gradually becomes less until;, when the brake-pipe 
pressure becomes enough greater than that in the auxiliary to 
overcome the friction on the packing ring 12 (Fig. 3), the pis- 
ton automatically moves back and seats the graduating valve. 

Q. Does the slide valve move? 

A. No^ not now. 
Q. Why not? 

A. The brake-pipe pressure was just strong enough to over- 
come the friction on the packing ring 12, move the piston 
back, and close the graduating valve. With the ports all 
closed, the piston would also have to compress the air in the 
auxiliary to go back any farther. Then, too, the pressure 
left in the auxiliary-reservoir, acting to force the slide valve 
on its seat produces a friction, if the valve were moved that 
the brake-pipe pressure as it stands is not sufficiently strong 
to overcome. 

Q. How do the auxiliary reservoir and brake-pipe pres- 
sures now stand? 

A. Practically equal although the auxiliary pressure had 



32 Air-Brake Catechism 

to be a trifle less to allow the triple piston to be moved back 
sufficiently to seat the graduating valve. 

Q. The brake is now partially applied and the triple 
is on what is termed lap position; what must be done to 
apply the brake harder? > 

A. Another reduction of brake-pipe pressure must be made. 

Q. How does this set the brake tighter? 

A. The auxiliary pressure once more being greater than 
that in the brake-pipe forces the triple piston down until it 
is again stopped by the graduating post. This movement is 
just sufficient to unseat the graduating valve the slide valve 
remaining where it was with its service port 'p (Fig. 2) in 
front of that to the brake cylinder. About the same amount 
of air pressure passes from the auxiliary to the cylinder that 
was taken from the brake-pij)e and the piston once more hav- 
ing a trifle more pressure on the brake-pipe than on the auxil- 
iary side moves back sufficiently to seat the graduating valve. 

Q. How long can these brake-pipe reductions continue 
to be made and cause the brake to set harder? 

A. Until the pressures have finally equalized between the 
auxiliary-reservoir and the brake cylinder. 

Q. After the auxiliary and brake-cylinder pressures 
were equal, would the brake set any harder if all brake- 
pipe pressure were allowed to escape to the atmosphere? 

A. Xo; when the brakes are fully set the auxiliary-reser- 
voir and brake-cylinder pressures are equal^ and a further re- 
duction of brake-pipe pressure would only be a waste of air 
that the pump would have to replace to release the brakes. 

Q. If a further brake-pipe reduction were made after 
the brake was fully set, would piston 5 (Fig. 1) move any 
farther than until the piston and graduating post 
touched? 

A. Yes; the spring 9 could not withstand the auxiliary- 



FUN^CTIONS OF THE TRIPLE VaLVE 33 

reservoir pressure, as it is so much in excess of the reduced 
brake-pipe pressure, and the piston would move down until 
it seated on gasket 11. In this position there would be a direct 
connection by the end of the slide valve between the auxiliary- 
reservoir and brake cylinder, but the brake would not set any 
tighter, as the auxiliary-reservoir, and brake-cylinder pres- 
sures were already equal. 

Q. The brake is now fully set. What is necessary to 
release it? 

A. It is necessary to get the pressure on the brake-pipe side 
of the triple piston greater than that on its auxiliary-reser- 
voir side. 

Q. How is this done? 

A. By moving the handle of the engineer's valve so as to 
connect the pressure, stored in the large main reservoir on the 
engine, with the brake-pipe. Air flowing from the main res- 
ervoir into the brake-pipe causes the pressure on the side of 
the triple piston to be sufficiently strong to overcome auxilary- 
reservoir pressure and force the triple piston to release posi- 
tion. 

Q. When the triple is forced to release position the 
slide and graduating valves are carried with it. What 
two port openings are made in this position? 

A. One between the brake-pipe and auxiliary-reservoir 
through the feed ports m and n (Fig. 1) ; and one from the 
brake cylinder to the atmosphere through ports d, e, f, g, li 
and Tc. The triple is in release as shown in the cut. 

Q. We notice that the feed grooves m and n (Fig. 1) 
are very small. How long would it take to charge an 
auxiliary reservoir from zero to seventy pounds with a 
constant pressure of seventy pounds in the brake-pipe, 
using the triple now sent out? 

A. About seventy seconds ; and occasionally a little longer. 



34 Aie-Brake Catechism 

Q. Will it charge more quickly than this with a 
greater pressure than seventy pounds in the brake-pipe? 

A. Yes. 

Q. Had we a train of fifteen cars, could we charge the 
fifteen auxiliary reservoirs as fast as we could one? 

A. Xo, because we now have fifteen feed grooves in the 
triples drawing air from the brake-pipe, and the pump cannot 
compress air fast enough to keep the brake-pipe pressure at 
seventy pounds. 

Q. Why not make these feed grooves larger so as to 
charge the auxiliary reservoirs more quickly? 

A. The purpose is to make the grooves sufficiently small 
that on a long train the auxiliaries will charge as nearly as 
possible alike. On a long train there is a tendency for the 
head auxiliaries to charsre much faster than the rear ones, if 
the triple feed grooves are larger than those now used. 

Q. What is likely to happen if some auxiliary reser- 
voirs charge faster than others? 

A. As the air is fed from the main reservoir back into the 
brake-pipe until those pressures are equal, and as the pump 
will not, on a long train, supply air as fast as the triple feed 
grooves take it from the brake-pipe, it follows that the auxil- 
iaries which charge the slower will continue to feed from the 
l)rake-pipe and cause a reduction that will set some of the 
head brakes. 

Q. So far we have spoken of the action of the plain 
triple only in the service application. What is the differ- 
ence in the action between the service and the emergency? 

A. In service the brakes set gradually, while in emergency 
they go on very suddenly. 

Q. A gradual reduction sets the brakes in service. 



Functions of the Triple Valve 35 

What kind of a reduction is necessary to set the brakes 
in emergency? 

A. A sudden reduction. 

Q. Describe the emergency action of the plain triple. 

A. The suddenness of the brake-pipe reduction causes piston 
5 (Fig. 4) to move down suddenly, striking the stem 8 a 
quick, sharp blow which the graduating spring 9 is not stiff 
enough to withstand. The piston travels down full stroke 
and bottoms on gasket 11. This is emergency position, and 
the slide valve has been drawn down so that air coming 
through Y from the auxiliary-reservoir passes by the end of 
the slide valve directly into the large port / leading to the 
brake cylinder without first going through the small service 
port p in the slide valve, as it did in the service position. 

Q. Why does the brake set more quickly? 

A. Because the air goes directly to the cylinder thi^ugh 
a larger port than is used in service. 

Q. Do we gain any more pressure with the plain triple 
in emergency than in full service? 

A. No ; in both cases the auxiliary-reservoir pressure equal- 
izes with that in the brake cylinder, but in emergency these 
pressures equalize more quickly because of the air reaching 
the brake cylinder through a larger port. 

Q. Are plain triples still used? 

A. Yes, but they are used almost entirely on engines and 
tenders. Their use on cars is confined principally to a very 
few of those equipments put on before the quick-action triple 
was introduced. 

Q. Where triples are used, is a plain triple valve 
always used on tenders? 

A. N"o; the present practice is to use a plain triple valve 
on the tenders of freight and switch engines; on the tenders 



36 Air-Brake Catechism 

of passenger engines a quick-action triple valve is be^'ng used 
more generally. 

Q. What has led to the use of a quick-action valve on 
passenger-engine tenders? 

A. The general introduction of the high-speed brake in 
passenger, mail^ and express service is responsible for this 
practice having become general^ although some roads have 
been using quick-action triples on their tenders in both 
freight and passenger service for some time. The quick-action 
triple on the tender is especially desired to help carry a sud- 
den reduction through the second engine in an emergency ap- 
plication when double-heading. 

Q. Is present equipment being fitted with plain or 
quick-action triple valves. 

A. Xeither, the ET engine and tender equipment is being 
almost exclusively applied. 

QUICK ACTION TEIPLE VALVK 

Q. When and by whom was the quick-action triple 
invented? 

A. In 1887, by George Westinghouse. 
Q. We have already had the plain triple valve. Why 
was the quick-action triple valve necessary? 

A. The plain triple valve was satisfactory so long as only 
the service application was used, but not so with the emer- 
gency application on a long train. In this latter case the 
head brakes were fully set so much sooner than those on the 
rear, that the slack of the train ran ahead and often did 
great damage. 

Q. What two important advantages are gained by the 
quick-action triple valve? 

A. We are enabled by the quick-action feature to set the 




likif^^^M 



SLIDE 
VALVE 




ATMOSPHERIC 
PRESSURE 



G. 4 A. The Old Standard Quick-Action Triple Valve. Release and Charging 

Position. 



Quick-Action Triple Valve 



37 



brakes throughout the train before the slack has a chance to 
run ahead and do damage, and not only does the brake set 
more quickly in emergency, but it is also set harder, tiius per- 
mitting a quicker stop and a higher safe speed for trains. 




to TRAIN riPf 
*"fip£ tap 



Fig. 5. — Quick- Action Triple Valve, Release Position. 



Q. In the use of the service application, vsrhat is the 
difference between the action of the plain and the quick- 
action triples? 



38 



Aie-Beake Catechism 



A. Xone whatever; their action and the parts employed 
are identical, excepting the additional ports placed in the 
slide valve of the quick-action triple, which are used only in 
emergency. 




Fig. 6. — Quick-Actiox Triple Valve, Service Position. 

Q. Will these two kinds of triples scattered through 
a train work together properly in service? 
A. Perfectly. 



Quick-Action Triple Valve 



39 



Q. Name the different parts of the quick-action triple 
not found in the plain triple. 

A. The strainer 16 (Fig. 5). The additional port 



^31 

TO BRAKE 

"cylinder 




TO TRA N PIPE 
I PIPE TAP 



Fig. 7. — Quick-Action Triple Valve, Lap Position, 



s in the slide valve and the removed corner of the slide valve 
shown in Fig. 10. 8 is the emergency piston. 10 is the 
emergency or^ as it is more commonly called, the rubber-seated 



-10 Aie-Beake Catechis:m 

valve. 15 is called the brake-pipe check, also the emergency 
check. 

Q. Of what use is the strainer 16, Fig. 5 ? 
A. Strainer 16 is to keep dirt from getting into the triple 
in such a way as to close the small feed ports i and Jc. 
Q. Of what use is piston 8? 

A. If the triple is moved so as to allow auxiliary-reservoir 
pressure to get into port t on top of piston S, this piston will 
be forced down, thereby forcing the emergency valve 10 from 
its seat. 

Q. What is done when the rubber-seated or emergency 
Valve 10 (Fig. 8) is forced from its seat? 

A. All air escapes from cavity Y and allows brake-pipe 
pressure to force the brake-pipe check 15 from its seat. 
Q. Of what use is the check valve 15? 
A. If a hose breaks in the brake-pipe, the brakes would 
fully apply on the whole train and, with no air in the brake- 
pipe, were it not for the check valve 15, brake-cylinder pres- 
sure coming in at c would force valve 10 from its seat and 
pass directly to the brake-pipe through cavity Y and out of 
the broken or parted hose releasing all of the brakes. 

Q. Explain the action of the quick-action triple in 
emergency. 

A. A quick brake-pipe reduction causes the auxiliary pres- 
sure to force the triple piston out the full length of chamber 
h (Fig. 8), the graduating spring 22 being compressed on ac- 
count of its inabilitv to withstand the sudden blow from the 
triple piston. 

With the triple piston in the extreme position to the left, 
or that of emergency, port s of the slide valve is in front of 
port r, thus establishing a connection between the auxiliary 
and brake cylinder. At the same time the removed comer of 
the slide valve, shown in Fig. 10, is in front of port t leading 
to the top of the emergency piston 8. The auxiliary pressure 



Quick-Action Triple Valve 41 

forcing piston 8 down unseats the emergency valve 10. This 
valve being unseated allows all pressure to escape from cav- 
ity Y. With no pressure in cavity Y to hold the brake-pipe 
check to its seat^ the brake-pipe pressure under the check 
raises it and passes into cavity Y over seat of valve 10 to cav- 
ity X and out at c into the brake cylinder; at the same time 
the auxiliary pressure is entering the cylinder through port r. 
As soon as the pressures equalize, piston 8, valve 10, and 
check 15 go to their normal positions. 

Q. Of what use are Figs. 9 and 10? 

A. Fig. 10 gives a better idea of the location of the ports 
in the slide valve; Fig. 9, the location of the ports in the 
bushing inside of which the slide valve works. 

Q. Name the parts. 

A. 26 (Fig. 5) is the drain plug; 16, the brake-pipe strain- 
er; 20, the graduating nut; 21, the graduating stem or post; 
22, the graduating spring; 4, the triple piston; j^ the piston 
stem; i and Ic, the feed ports; 6, the slide-valve spring; 3, 
the slide valve; 7, the graduating valve; w, the service or 
graduating port; n, the exhaust port; s, the emergency port; 
z, a continuation of the service port w; 15, the brake-pipe or 
emergency check; 12, the brake-pipe check spring; 10, the 
emergency or rubber-seated valve; 8, the emergency piston. 
The exhaust port p leads around outside the brass bushing 
to the atmosphere as shown in Fig. 9 by the dotted lines. 

Q. What views do Figs. 5 to 8 represent? 

A. The triple valve in its four positions: release, service, 
lap, and emergency positions. 

Q. We have seen that with the quick-action triple the 
brakes are set harder in emergency. Are brakes set in 
emergency any harder to release? 

A. They are with quick-action triples only. 

Q. Why? 

A. With the quick-action triples air from the brake-pipe 



42 



Aie-Brake Catechism 



helps set the brakes in emergency, and the pressures equalize 
higher ; therefore the brake-pipe pressure must be made high- 
er to overcome the auxiliary-reservoir pressure and force the 



TC E=iKt 




Fig. 8. — Quick-Action Teiple Valte, E.mergexcy Position. 



triple piston to release position. With the plain triple the 
pressures equalize at the same pressure as in service. 

Q. In Fig. 5 a packing ring 31 is shown in the emerg- 



Quick-Action Triple Valve 



43 



ency piston. Is this ring found in all quick-action triple 
valves? 

A. It is in all modern passenger triples but not in freight 
valves. The small port in piston 8 is also found in pas- 
senger valves only. 




Fig. 9. — Slide Valve Bushing. 

Q. After a partial service application has been made, 
can we get the quick-action? 

A. This depends on the amount of reduction that has 
been made in service and upon the piston travel. In no case 
can we gain as much after making even a small service re- 
duction as we could if the sudden reduction were made when 
the auxiliary-reservoirs were fully charged and the brakes 
released. 




Fig. 10. — Slide Valve. 



After a light reduction a gain over the pressure obtained 
in full service can be made by going to emergency position 
if the piston travel is a fair length, but not with short travel. 

By using the emergency after a partial service applica- 



44 Air-Brake Catechism 

tion, even we made no gain of pressure, we would get the 
full service more quickly. 

Q. How quick must a reduction be made in the brake 
pipe to throw a triple into quick-action? 

A. Faster than the auxiliary-reservoir pressure can get to 
the brake cylinder through the service port in the slide valve. 
In this case the graduating spring will not hold the triple 
piston from traveling full stroke. 

Q. When a triple is thrown into quick-action which 
pressure, auxiliary reservoir or brake pipe, reaches the 
brake cylinder first? 

A. Just a jElash of auxiliary-reservoir pressure reaches the 
cylinder as the service port in the slide valve passes the port 
leading to the cylinder, but the air from the brake-pipe reaches 
the cylinder first in any considerable volume, as the corner 
cut off from the slide valve allows the auxiliary-reservoir pres- 
sure to strike piston 8 and force the rubber-seated valve 10 
from its seat before port s comes in front of port r, 

Q. Why is port s (Pigs. 8 and 10), used in emergency, 
made smaller than port z, used in service, to let auxiliary 
reservoir pressure into the brake cylinder? 

A. So as to hold the auxiliary-reservoir pressure back in 
emergency and allow as much air as possible to enter the brake 
cylinder from the brake-pipe. 

Peculiarities axd Troubles of the Quick-Action 

Triple Valve. 

From what follows it may seem that a triple will get out of 
order under the slightest provocation. This, however, is not 
true; it is a constant source of wonder to see the fine action 
of triple valves which have little or poor care. A triple needs 



Quick-Action Triple Valve 45 

no more care than any other piece of mechanism to keep it 
doing first-class work. The aim of what follows is to bring 
out its possibilities. 

Q. What could wholly or partially stop the charging 
of an auxiliary reservoir? 

A. The strainer in the brake-pipe where the cross-over 
pipe leading to the triple joins the main brake-pipe, or the 
strainer 16 in the triple (Fig. 5) being filled with dirt^ scale, 
cinders or oil. Port i ot h might be plugged, the triple might 
be cut out, or there might be a leak in the auxiliary-reservoir 
which let the air out as fast as it came in. 

Q. If all auxiliary reservoirs did not charge equally 
fast, what would be the effect? 

A. If we wished to apply the brakes very soon, the ones 
with the auxiliary-reservoirs not fully charged would not re- 
spond to the first reduction if light. 

Q. Occasionally after coupling up the hose in a train 
it is found that the brake on a car will not apply in re- 
sponse to a reduction of brake-pipe pressure. What might 
be the trouble other than those just described? 

A. It sometimes happens that the switch crew is respon- 
sible for such an occurrence. Sometimes when an air train 
is brought into a yard and the yard crew is in a hurry to 
^^drilF^ the train with an engine not equipped with air, they 
do not always bleed the train in the proper manner. In- 
stead of opening an angle cock and then bleeding all the 
reservoirs by hand, they put a piece of coal or wood under 
an arm of the auxiliary-reservoir release valve to do the work 
of holding the valve from its seat. In this way they save 
time for themselves but are a source of considerable bother 
to the ones who inspect the train. On account of the air 
escaping through a comparatively large port, the leakage 
is not always detected without a careful examination. 



46 Air-Brake Catechish 

Q. Will any other trouble result from the strainers 
being corroded or dirty? 

A. Yes ; we might not be able to make a sufficiently quick 
reduction on the triple piston to get quick-action. 

Q. One triple going into quick-action makes a sud- 
den brake-pipe reduction which starts the next triple, 
and that one the next, and so on throughout the train. 
If five or six cars together in the train were cut out, or 
had plain triples, or very dirty strainers, would the triples 
back of these go into quick-action when the engineer 
made a sudden reduction? 

A. Xo, on account of the resistance of friction to the pas- 
sage of the sudden reduction through the six car lengths of 
pipe. The friction gradually destroys the suddenness of the 
reduction, and there is onlv a slio^ht and o:radual reduction, 
in the brake-pipe back of the cars cut out. 

Q. What bad effect would follow if the engineer did 
not continue making a reduction? 

A. The air coming ahead from the back of the train would 
release the head brakes. 

Q. Could these brakes in the back of the train be ap- 
plied? 
A. Yes, in service but not in emergency. 

Q. Water sometimes collects in cavity 13 (Fig. 5) of 
the triple. Where does it come from? 

A. It comes into the brake-pipe as vapor in the air, and 
condenses whenever a sudden drop in brake-pipe pressure oc- 
curs. 

Q. What bad effect will water have in this place? 

A. It is likely to freeze in winter and block the flow of air 
through the triple. 

Q. What should be done in such a case? 

A. Apply burning waste and when thawed remove the 



Quick-Action Triple Valve 47 

drain plug 26 to remove the water or the trouble will recur. 
Q. What would be the efifect of a weak or broken 
graduating spring? 

A. We would have nothing to stop the triple piston when 
it reached service position, and it would move on to emergency 
position. 

Q. If one triple goes into quick-action, will the rest go? 

A. Yes, as a sudden reduction is made on the brake-pipe 
through the emergency ports of the triple in this case. This 
sudden reduction starts the next and that the next and so on. 

Q. Will a weak or broken graduating spring always 
throw the triples into quick-action? 

A. No, only on a short train. 

Q. Why not on a long train? 

A. On a short train, with a gradual brake-pipe reduction, 
air is drawn from the brake-pipe faster than the auxiliary 
reservoir pressure can get to the brake C3dinder through the 
service port of the slide valve. When the auxiliary-reser- 
voir pressure is enough greater than that in the brake-pipe, 
it forces the triple piston to emergency position, as there 
is no graduating spring to stop it. 

On a long train, it takes longer to make a corresponding 
reduction on account of the larger volume of air in the brake- 
pipe. This gives the auxiliary-reservoir pressure longer to 
pass into the cylinder, and as a result the brake-pipe and 
auxiliary-reservoir pressures keep about equal and the triple 
piston will not move to emergency position unless a sudden 
reduction is made. 

Q. How many air cars must there be in a train so that 
a broken or weak graduating spring will not affect the 
service application? 

A. Usually not less than six or seven; with more than 
this number, if otherwise the triples work properly, the grad- 



48 Air-Brake Catechism 

uating springs could be removed from all triples and no bad 
effect be noticed. 

Q. What two things will cause the triples to go into 
quick-action regardless of the length of the train? 

A. A sticky triple or a broken graduating-valve pin. (The 
one which fastens the graduating valve to the piston stem 
as shown by the dotted lines, Fig. 5.) 

Q. Why will a sticky triple throw the brakes into 
emergency? 

A. Because the triple does not respond to a light reduc- 
tion. When it does move it jumps, and the sudden blow 
compresses the graduating spring and the triple is in the 
quick-action position. This car starts the rest as before 
explained. 

Q. Why will a broken graduating pin throw the 
brakes into emergency? 

A. Because with this pin broken there is nothing to move 
the graduating valve from its seat when the triple piston 
moves and the auxiliary-reservoir pressure is acting to hold 
it on its seat. When a brake-pipe reduction is made and 
the triple assumes service position, no air can leave the auxil- 
iary-reservoir and pass through the graduating or service port 
of the slide valve, as the graduating valve is on its seat. When 
sufficient brake-pipe reduction has been made so that the 
graduating spring cannot withstand the auxiliary-reservoir 
pressure acting on the piston, the triple goes to the quick- 
action position, and we get the quick-action on this car and 
consequently on the rest as before explained. 

Q. Which of these three troubles — ^weak graduating 
spring, broken graduating pin or sticky triple — will 
usually be found to exist if the brakes go into emergency 
with a service reduction? 

A. A sticky triple, and this usually means that the triple 
causing the trouble has had poor care. 



Quick-Action Triple Valve 49 

Q. Shall we get the same result regardless of the loca- 
tion of the faulty triple in the train? 

A. Yes; if one starts, all do. 

Q. What is the probable trouble with a brake which, 
when set in service, will sometimes remain set and some- 
times release? 

A. A dirty slide valve which sometimes seats properly and 
at others not; in the latter case auxiliary-reservoir pressure 
escapes to the atmosphere through the exhaust port and al- 
lows brake-pipe pressure to force this triple to release position. 

Q. How may this defect be remedied? 

A. Eemove the triple piston and attached parts, clean care- 
fully, loosen the packing ring without removing and rub a 
little oil on the slide valve with the finger. 

Q. Why not pour on the oil? 

A. Too much oil is bad, as it collects dust, which with the 
oil forms gum. This causes a triple to stick. 

Q. What effect will a moderate leak in the brake pipe 
have if the brakes are not set? 

A. It will simply cause the pump extra work to supply it. 

Q. What effect if the brakes are set? 

A. It will cause them to apply harder. 

Q. Will the leak cause only the brake on that car to 
leak on, or all? 

A. All, as the brake-pipe is continuous through the train. 

Q. What effect will a leak in an auxiliary reservoir 
have if a brake is released? 

A. It will keep the pump at work the same as a brake-pipe 
leak. 

Q. What effect if the brakes are applied? 

A. It will leak the brake off on the car where the leak is 
and, then, drawing air from the brake-pipe through the feed 
ports, it will gradually set the other brakes tighter. 



50 Air-Brake Catechism 

Q. There are a number of leaks in the triple which 
will cause a blow at its exhaust port. Name the two most 
likely to produce this effect. 

A. A leaky slide valve or a leaky rubber-seated valve (Fig. 
5). 

Q. How can we tell which of these is causing the 
trouble? 

A. As the exliaust port in the slide-valve seat is always 
in communication with the atmosphere, whether the brakes 
are applied or released, a leak by the face of the slide valve 
will cause a constant blow. 

Q. How else can we tell if it is the slide valve that 
causes the trouble? 

A. Apply the brake, and if auxiliary-reservoir pressure is 
leaking away under the slide valve, the brake will generally 
release. 

Q. How can we tell if the trouble is with the rubber- 
seated valve? 

A. The rubber-seated valve will cause a blow at the ex- 
haust only when the brake is released. 

Q. Why? 

A. The rubber-seated valve 10 (Fig. 5) leaking will allow 
the pressure to leave cavity I^. The brake-pipe pressure then 
raises check 15 and passes through cavity I^ past the rubber- 
seated valve, through cavity x, ports c and r, into the exhaust 
cavity ?? of the slide valve and out to the atmosphere through 
port p. When the brake is applied, port n in the slide valve 
is closed to port r, consequently the blow stops. 

Q. Where does the air which is leaking past the rub- 
ber-seated valve go after the brake is applied? 

A. Direct to the brake cylinder through c, and this brake 
continues to set harder. 



Quick-Action Triple Valve 51 

Q. Why is a leaky rubber-seated valve more likely to 
slide the wheels on a car in a long train than in a short 
one? 

A. After the brakes are applied^ this leak allows the brake- 
pipe and brake-cylinder pressures to equalize. With a long 
brake-pipe there is a much greater volume of air, and these 
pressures will equalize higher. 

Q. How else can we tell if the rubber-seated valve 
leaks? 

A. Turn the cut-out cock in the cross-over pipe from the 
brake-pipe to the triple after everything is charged: if the 
rubber-seated valve leaks, it will draw air from the brake- 
pipe ; with the cut-out cock closed, this leak is not being sup- 
plied, and the reduction will cause the brake on this car to 
apply. 

Q. Give another symptom which indicates a leaky rub- 
ber-seated valve. 

A. The leak above the check 15 caused the check to rise to 
supply it, and when the cavity is again charged the check 
closes. It sometimes rises and closes so fast as to make a loud 
buzzing sound. 

Q. What is usually the cause of leaking in a rubber- 
seated valve? 

A. Dirt on the seat, a poor seat caused by wear, the use of 
oil on the quick-action part of the triple, or using too much 
oil in the brake cylinder, which will work into the triple and 
cause the rubber to decay. 

Q. If dirt is the source of the trouble, how may it be 
removed without taking the triple apart? 

A. Set the brake by opening the angle cock after closing 
the cock at the other end of the car. If there is dirt on the 
valve, it may be blown off in this way. 



52 Air-Brake Catechism 

Q. What besides the slide and rubber-seated valves 
will cause a blow at the exhaust port of the triple? 

A. Gasket 14 (Fig. 5) leaking between e and cavity X, 
or the gasket leaking between the brake cylinder and auxil- 
iary-reservoir where the triple is bolted to the cylinder. On 
freight equipments there is a pipe which runs inside the 
auxiliary to the brake cylinder; this pipe leaking will also 
cause a blow. 

Q. Are these leaks common? 

A. On the contrary they are very uncommon. The blow 

is almost invariably due to a leaky slide or emergency valve. 

Q. What effect would the leaking of graduating valve 

7 (Fig. 5) have? 

A. The action produced by such a leak is uncertain, and 
depends greatly on the conditions connected with it. When 
the brake is applied, the triple assumes lap position after the 
auxiliary-reservoir pressure is a trifle less than that in the 
brake-pipe. If the graduating valve leaks, the auxiliary-res- 
ervoir pressure gradually reduces, and the brake-pipe pressure 
forces the triple piston and slide valve back until the blank 
on the face of the slide valve between ports 2 and n is in front 
of port r. If the graduating valve does leak, no more air can 
leave port z in this position, and the slide valve stops. This 
blank space is only, a trifle wider than port r, so if the valve 
is in good condition and works smoothly, the brake should 
not release; but if it works hard, it is likely to jump a little 
when it moves, and open the exhaust port. 

Q. Give a rule by which to tell how a leaky graduat- 
ing valve will act. 

A. If the triple is in proper condition, a leaky graduating 
valve should not release a brake. If the triple is a trifle sticky, 
a brake is likely to be released. A leaky slide valve or m 
slight auxiliary-reservoir leak in combination with a leakinj 



Type "K'' Triple Valve 53 

graduating valve will' release a brake. The action also de- 
pends upon the condition of the triple-piston packing ring 
which if comparatively loose will permit brake-pipe pressure 
to feed into the auxiliary-reservoir as fast as its pressure es- 
capes. If brake-pipe and auxiliary-reservoir pressures remain 
equal^ the triple piston is not affected^ and the leakage by 
the graduating valve would not release the brake. 

THE TYPE ^^K^^ TRIPLE VALVE. 

Q. What does Fig. 11 illustrate? 

A. Fig. 11 illustrates the improved K triple valve which 
is now superseding the former quick-action triple valve in 
freight service. 

Q. Does this triple valve differ any in principle of 
operation from the old standard valve? 

A. No; it operates on the same principle^ that is, a re- 
duction of brake-pipe pressure causes the brake to apply and 
an increase of brake-pipe pressure causes it to release. 

Q. What are the important advantages of the im- 
proved valve over the old? 

A. With the improved valve a portion of the brake-pipe 
air is vented to the brake cylinder in each service application ; 
this causes a quicker fall of pressure in the brake-pipe 
throughout the train and hence a quicker serial application 
of the brakes than is now obtained with the older form of 
triple. In the release of the brakes on long trains those on 
the front portion may be held applied until those in the rear 
have been released; this action causes the slack to settle in 
instead of stretching out, which latter action tends to break 
the train in two. There is also a uniform recharge feature 
by means of which the recharge at the head end is slowed 
up. This makes available a greater amount of air with which 



S4 



Air-Brake Catechism 



to release and recliarge the brakes at the rear of the train; 
it also does awaj^ with the overcharge of the auxiliary reser- 
voirs at the front of the train, which overcharge usually 
results in the reapplication of the brakes near the engine 
when the brake valve handle is moved to running position. 
The reapplication wastes air and overheats wheels because 
of extra amount of work performed. 




Fig. 11. — K Triple Valve — Exterior View. 



Q. What oth^r advantages are obtained with the K 

triple? 

A. There is a large saving in the quantity of air used 

which results in less pump labor, the brakes apply more uni- 
formly and with greater certainty on the longest trains and 
with any service reduction desired. In heavy grade work 
there is much less chance for the engineer to "lose his air^' 
and of the train running away in consequence. 

Q. In the emergency application of the brake is there 
any advantage of the new triple valve over the old? 

A. The emergency feature of the triple has not been 



Type ''K'' Triple Valve 



55 



changed and the results that can be obtained with the valves 
are practically identical. 

Q. In service application using a brake-pipe pressure 
of 70 pounds, how much reduction is necessary to set the 
brakes in full? 

A. About 17 pounds, 3 pounds less than with the standard 
triple. 

Q. Will these triples give satisfactory results in brak- 
ing when intermingled in any considerable number with 
the older triples? 




Fig. 12.— K Triple Valve- 
Ckoss Section. 



56 Air-Brake Catechism 

A. Yes, and on long trains they will very materially im- 
prove the action of the older triple. 

Q. What does Fig. 12 represent? 

A. It is a vertical cross section of the K triple representing 

the interior construction. 

Q. What are the names of the diflferent parts of the K 
triple as numbered on this cut? 

A. 2, Valve Body; 3, Slide Valve; 4, Main Piston; 5, 
Main-Piston Packing Eing; 6, Slide-Valve Spring; 7, Grad- 
uating Valve; 8, Emergency Piston; 9. Emergency-Valve 
Seat; 10, Emergency Valve; 11, Emergency- Valve Eubber 
Seat; 12, Check- Valve Spring; 13, Check- Valve Case; 14, 
Check- Valve Case Gasket; 15, Check Valve; 16, Air Strain- 
er; IT, Union Xut; 18, Union Swivel; 19, Cylinder Cap; 20, 
Graduating Stem-Xut; 21, Graduating Stem; 22, Graduating 
Spring; 3, Cylinder-Cap Gasket; 24, Bolt and Xut; 25, Cap 
Screw; 26, Drain Plug; 27, Union Gasket; 28, Emergency- 
Valve Xut; 29, Eetarded-Eelease Stem; 32, Ectarded-Eelease 
Spring Collar; 33, Eetarded-Eelease Spring; 34, Eetarded-Ee- 
lease Stem Pin; 35, Graduating- Valve Spring. 

Q. What is represented in Fig. 13? 

A. A face view of the graduating valve, a face view and a 
top view of the slide valve, and a view of the slide-valve 
bush, with their ports, cavities, etc., arranged as actually con- 
structed. 

Q. What is represented in Figs. 14 to 18 inclusive? 

A. These figures are diagrammatic drawings intended to 
show clearly the relation of the various ports and passages in 
the different operative positions of the valve. 

Q. Explain the operation of the triple as shown in 
Pig. 14. 

A. Full release position is shown in Fig. 14. Brake-pipe 
air enters the triple-valve body at the connection marked BP, 



Type ''K'' Triple Valve 



57 



passes upward through passage^ a, e, f and g to chamber h, 
thence through the feed groove i past the triple piston into 
chamber R and out to the auxiliary reservoir. Brake-pipe 
air also flows past the non-return check valve, from chamber 



&' 



tace: view 
GRADUATING VALVE . 






^yt 



rACE VIEW 






TOP VIEW 

SLIDE VALVE. 



.K-^^^K-N^^^-^^^^-^-K- ^^;^;!^^ 



^f) Of!: 



t>^^<^^^<^^^^<^^^<^ 



SLIDE VALVCBUSH. 



Fig. 13. — K Triple Valve. 

a into chamber Y, thence through passage y in the body and 
port j in the slide valve to chamber R and the auxiliary reser- 
voir. In this way the auxiliary reservoir is charged up to the 
pressure in the brake pipe. The slide valve is shown in this 
figure with its exhaust cavity n uncovering wide the exhaust 



58 



Air-Beake Catechism 



port in the slide-valve seat leading from the brake cylinder 
to the atmosphere^ providing for the release of the brake 
through port r, cavity n, and port p. 

Q. What is shown in Fig. 15? 

A. In this figure^ the parts of the K triple are represented 
in the service position, the position they assmne while a serv- 
ice reduction in brake-pipe pressure is being made. 

Q. Explain the operation in service position. 

A. The triple piston, as shown, has moved toward the 



Y.w/^y/^wA 




Fig. 14. — K Triple Valve — Full Release. 



left until it touches the graduating stem, and it has carried 
with it the main slide and the graduating slide valves. Port z 
in the main slide valve registers with port r in its seat. Port z 
is uncovered by the graduating valve so that air is free to flow 
from the auxiliary reservoir to the brake cylinder. At the 
same time passage y and port o are in register, and cavity v 
in the graduating valve spans port o and q. Port q is in reg- 
ister with port i leading around the loosely fitting piston to 
chamber x and the brake cvlinder. Hence, arran^^cd as shown, 



Type ''K'' Triple Valve 



59 



these ports permit brake-pipe air to flow into the brake cyl- 
inder at the same time that the auxiliary reservoir is supply- 
ing air. 

Q. What does Fig. 16 represent? 

A. It shows the triple valve in what is termed the Service- 
Lap position. 

Q. When does the triple valve assume this position? 

A. When the pressure in the auxiliary reservoir falls 




Fig. 15. — K Triple Valve — Service Position. 



slightly below that remaining in the brake pipe. As shown 
in this figure the triple-valve piston has moved the graduat- 
ing valve back far enough to close ports o, q, and z, and thus 
prevent further flow of air from both the auxiliary reservoir 
and the brake pipe to the cylinder. It will be noted in the 
figure that the main slide valve is ahead of its position 
shown in Fig. 15. The valve would only assume this position 
if the brake-pipe pressure were reduced faster than the 
auxiliary-reservoir pressure could reduce to the brake cylinder. 



60 



Air-Brake Catechism 



otherwise port o would remain in register with port \j as in 

Fig. 15 but the graduating valve would have closed ports o 

and z as shown in Fi^f. 16. 

<^ 

Q. What is shown in Fig. 17? 

A. Fig. IT represents the different parts of the K triple 

in the Eetarded-Eelease position. 

Q. How are they made to assume this position? 

A. By admitting main-reservoir air to the brake pipe fast 







Fig. 16. — K Triple Valve — Sertice-Lap Position. 



enough to increase the pressure considerably above that re- 
maining^ in the auxiliarv reservoir. 

Q. Explain the operation in the retarded release 
position. 

A. As shown brake-pipe pressure forces the triple piston 
to the extreme right until it strikes against the slide-valve 
bush. \Mien this occurs brake-pipe air feeds only through 
charging groove \ and the small port / in the end of the sUde- 
valve bush to reach the auxiliary reservoir. 



Type ''K'' Triple Yalve 



61 



The triple-piston stem abuts against the retarded-release 
spring and partially compresses it. The slide valve has 
moved far enough over to bring the restricted port n (Fig. 
13)^ the exhaust cavity, over exhaust port p^ thus reducing 
very materially the size of this port, causing a slow release of 
the brake. In a long train this retarded release can^ if de- 
sired, be obtained about 30 cars back in the train. 

Q. What is it that causes the triple piston to assume 
the retarded-release position? 



'^////y^//A^A>//y^^////A 




Fig. 17. — K Triple Valve — Retarded Release Position. 



A. To cause the piston to assume this position it is neces- 
sary to have the pressure on the brake-pipe side of the triple 
piston sufficiently in excess of that in the auxiliary reservoir 
to permit of the greater pressure acting on the brake-pipe 
side of the piston to compress the retarded-release spring. 
With the usual main-reservoir pressure and capacity, it is 
possible to compress this spring on a long train about thirty 
cars back. The effect of the friction due to the flow of air is 
to prohibit any rapid rise of brake-pipe pressure back in 



62 



Air-Brake Catechism 



the train but^ as already stated^ the desired differential be- 
tween the brake pipe and auxiliary-reservoir pressure can be 
obtained about thirty cars back in a 100-car train. 

Q. What does Fig. 18 represent? 

A. It represents the K triple in the Emergency position. 

Q. When does the valve assume this position? 

A. Whenever a heavy^ quick reduction in brake-pipe 
pressure is made, as when the brake valve is quickly placed in 
emergency position or a hose bursts. 




myw////Mm 






Fig. 18. — K Triple Valve — Emergency Position. 



Q. Explain the operation in emergency position. 

A. It is the same as that given for the standard triple. 
Air is admitted to the top of the emergency piston through 
the large port t. This piston is forced downward^ and brake- 
pipe pressure raises the non-return check valve, and flows 
quickly through ports r and C to the brake cylinder. At the 
same time port s in the slide valve registers with port r so 
that auxiliary-reservoir air can flow through this port also to 
the brake cylinder and will equalize with it. 



Type ''K'' Triple Valve 63 

Q. How many sizes of the K triple are there? 

A. Two, the K-1 and K-2. 

Q. On what size car equipment is the K-1 triple used? 
The K-2? 

A. The K'l is used on eight-inch freight equipment^ and 
the K'2 on ten-inch. 

Q. Can a K-1 and a K-2 triple be readily substituted 
for the older corresponding size of quick-action triple? 

A. Yes, they are perfectly interchangeable on their re- 
spective reservoirs. 

Q. On a train of eighty cars will a flve-pound service 
reduction set all the brakes? 

A. Yes, and a 5-pound reduction will be as effective in 
stopping an empty train from a speed of 20 miles per hour as 
a 2 3 -pound service reduction with the older triples. 

Q. Explain this. 

A. Because of the venting of brake-pipe air to the brake 
cylinder^ a five-pound initial reduction insures the aplication 
of all brakes on the train in a much shorter time than they 
can be applied with any service reduction with the older triples, 
and also with a higher pressure than can be obtained from a 
5-pound service reduction with the ordinary quick-action 
triple valve with which on this length of train only a com- 
paratively few brakes will apply. 

Q. Is there any difference in the internal construction 
of the K-l and the K-2 triples? 

A. In full release position, the charging takes place 
through the feed port i only with the K-1 triple, while the 
feed port i in the piston bush and port j in the slide valve 
are both used with the K-2 valve. Port ; does not exist in 
the K-1 triple. 



64 



Air-Brake Catechism 



Q. As to care and maintenance of the K triple, do the 
same rules apply as to the old standard triple? 
A. Yes. 

THE TYPE ''V TEIPLE VALVE. 

Q. What valve is illustrated in Figs. 19 and 20? 

A. The Type L Triple A' alve. 




Fig. 19.— "L" Triple Valve. 

Q. What kind of a triple valve is it, and in what ser- 
vice is it used? 

A. It is a new type of Quick-Action Triple Valve for use 
in High-Speed Passenger Service. 

Q. What feature does it have not found in the old 
standard quick-action triple valve already described? 

A. It lias the Graduated Release^ by means of which the 



Type ''U' Triple Valve 



65 



brakes in the train can be partially released when desired; 
(2) it has the Quick-Service, by means of which service ap- 
plications are obtained throughout long trains in much less 
time than with the old standard triple; (3) it has the Quick- 
Eecharge, by means of which the auxiliary reservoirs are re- 
charged during release of the brakes in the same time as the 
air can exhaust from the brake cylinder; (4) it obtains a much 




Fig. 20.— "L" Triple Valve. 



higher brake-cylinder pressure in emergency than with the 
old standard-triple valve. 

Q. Are the high-speed reducing valves used in connec- 
tion with the L Triple Valve? 

A. No ; they are unnecessary, as the L triple performs all 
tlie duties of a triple valve and high-speed reducing valve 
combined. The safety valve, which is a part of the triple 
valve, takes the place of the high-speed reducing valve. 



G6 



Air-Erakp: C^atechism 



Q. Is any additional apparatus required when the L 
Triple Valve is substituted for the old standard? 

A. Yes^ a ^^supplementary'^ reservoir^ about twice the size 
of an auxiliary reservoir, is required. 

Q. What is the purpose of the supplementary reser- 
voir? 

A. It furnishes the means of obtaining the graduated re- 




FiG. 21. — DiAGKAM OF Type L Triple Valye Release axd Ch arc- 
ing Position. 



lease, quick-recharge, and the high-emergency brake-cylinder 
pressure. 

Q. Is any other change of apparatus required when 
substituting the L Triple Valve? 

A. The brake-cylinder pressure head must be exchanged 
for one haYing all 2)ipe connections made in it, as the L Triple 
is of the '^pijDeless'^ type. 



Type ''U' Tiuple Valve 



67 



Q. What is the advantage of a ' ' pipeless ' ' triple valve? 

A. As all pipe connections are made to the cylinder 
pressure head^ and communicate with the triple valve through 
suitable jDorts in the head and triple-valve body^ the triple 
valve may be removed for inspection and repairs without 
breaking any pipe joints. 




ww^wmm ^ 



Pig. 22. — Diagram of Type L Triple Valve. Quick-Service 

Position. 



Q. How does the outside appearance of the L Triple 
differ from the old standard? 

A. There is a ^Vent-valve*^ portion which lies across the top 
of the body at right angles to the movement of the slide- 
valve; and a safety valve is attached vertically to one side. 
Also, there is no connection for pipes on the valve. 

Q. What are Figs. 21 to 26. 

A. They are diagrams of the L Triple Valve in different 



68 



Air-Brake Catechism 



positions^ witli the parts so arranged as to slio^v all the parts 
in one plane without regard to the actual construction of the 
valve. 

Q. Name the connections to the triple valve. 

A. Eef erring to Fig. 21, the brake pipe connects with 
passage a; passage C connects with the brake cylinder; port 




Fig. 23. — Diagram of Type L Triple Val\':e. Service-Lap 

Position. 



X connects with the supplementary reservoir; the slide valve 
cavity R is always connected to the auxiliary reservoir. 

Q. How is the passenger car brake charged up at 
starting? 

A. Air flows through the brake pipe from the locomotivel 
and enters the triple valve by passage a, e and g to cylinder li\ 
and through the feed groove i to chamber li and the auxiliarvi 



Type ''JJ' Triple Valve 



69 



reservoir; the air also lifts check valve 15 and enters chamber 
Y, thence through port y in the seat and / in the slide valve^ 
it flows to chamber R and the auxiliary reservoir; thus the 
latter is charged by two different channels giving a very 
prompt rise in the auxiliar}^-reservoir pressure. At the same 
tinie^ air flows from chamber R through port h in the slide 




Pig. 24. — Diagram of Type L Triple Valve. Full-Sekvice 

Position. 



valve and x in the seat to the supplementary reservoir charg- 
ing it at the same time to the auxiliary-reservoir pressure. 
The charging continues till both reservoirs and brali:e pipe 
are at the same pressure. 

Q. What happens in the triple valve when a moderate 
service reduction takes place? 

A. The reduction in brake-pipe pressure in cylinder li 
allows the higher pressure remaining in the chamber R to force 



70 



Air-Brake Catechism 



the piston, graduating valve and slide valve to the left (Fig. 
22) until the piston strikes the graduating sleeve 21, held in 
its place by graduating spring 22. Port y in the valve seat 
connects with port o in the slide valve, and the latter through 
a small cavity in the graduating valve, and port in the slide 
valve with cavity q, the latter connecting with port r and the 




Fig. 25.— Diagram of Type L Triple Valve. Release-Lap 

Position. 

brake cylinder. Consequently brake-pipe air lifts the check 
valve 15, and flows through cavity Y, port y and the connec- 
tions just mentioned to the brake cylinder. Not a large quan- 
tity of air, however, flows through this channel, for the 
reason that port z in the slide valve partially registers with 
port r in the seat, allowing auxiliary-reservoir air also to flow 
to the brake cylinder; and the size of the ports between the 
auxiliary reservoir and brake cylinder are larger than those 



Type "IJ' Triple Valve 



71 



between the brake pipe and the brake cylinder^ so that the 
larger amount of air for setting the brakes comes from the 
auxiliary reservoir. The small amount of air taken from the 
brake pipe helps to reduce its pressure, so that the reduction 
passes through the train more rapidly than with the old stand- 
ard equipment. This is the Quick-Service feature. 




Fig. 26. — Diagram of Type L Triple Valve. 

Position. 



Emergency 



Q. What is this position called? 

A. Quick-service position. 

Q. Does the triple valve remain in this position during 
the brake application? 

A. No. As soon as the auxiliar5^-reservoir pressure falls, 
by flowing into the brake cylinder^ to a point slightly below 
that remaining in the brake pipe, the piston and graduating 
valve are forced to the right until the piston strikes tlie slide 



72 Aie-Beake Catechis^i 

valve as shown in Fig. 23. In this position, both port z and 
the small port connecting with cavity q are closed by the 
graduating valve, so that no more air can flow to the brake- 
cylinder from either the auxiliary reservoir or the brake pipe. 

Q. What is this last mentioned position called? 

A. >Service-Lap Position. 
Q. Why SERVICE Lap? 

A. Because there are two lap positions in the L Triple 
Valve ; the Service Lap and the Eelease Lap. 

Q. Are there any other ports connecting in the Service 
or Lap Positions? 

A. Yes ; cavity q always connects port /• with port h in the 
seat^ in all service and lap positions. Port i leads to the 
safety valve on the side of the triple valve. 

Q. What is the object of this arrangement? 

A. So that the safety valve will protect tlie brake cylinder 
against too high pressure in all service applications. Since 
the triple valve is designed for the high-speed brake equip- 
ment, which employs 110-pounds pressure in brake pipe and 
auxiliary reservoir, it is necessary to limit the pressure in the 
brake cylinder to 50 pounds in service applications, as the 
braking power of the car is calculated for this amount ; if no 
safety valve or reducing valve was used, the 110 pounds in 
the auxiliary reservoir would equalize with the brake cylinder 
at about 85 pounds, which in the conditions of ordinary serv- 
ice stops, would likely cause the wheels to slide. 

Q. Is there any other service position than Quick 
Service? 

A. Yes; Full Service. 

Q. When a service reduction is made, what determines 
whether the triple valve will go to Quick Service or Full 
Service? 

A. The length of the train. 



Type ''1j'' Triple Valve 73 

Q. How is that? 

A. In a short train^ the vokime of the brake pipe is small^ 
and its pressure will therefore reduce more rapidly than a 
long train^ for the same reduction at the brake valve. Con- 
sequently^ when a service reduction is made with a short train, 
the fall of pressure in cylinder h of the triple valve, may be 
rapid enough to allow the piston, when moving to the left, 
to slightly compress graduating spring 22 when it strikes 
graduating sleeve 21, as shown in Fig. 24. In this positioii, 
port in the slide valve does not register with port y in the 
seat, so that no air flows from the brake pipe to the brake 
cylinder, except as the ports pass each other ; at the same time, 
port z is wide open to port r, allowing the auxiliary-reservoir 
air to flow more rapidly to the brake cylinder, so that its 
fall in pressure keeps pace with that in the brake pipe. In 
this way, the triple valve itself automatically cuts out the 
Quick-Service feature when the brake-pipe reduction is Guf- 
ficiently rapid without it. The piston and graduating valve 
go to Service-Lap position after the Full Service, in exactly 
the same manner as after the Quick Service. 

Q. What occurs in the triple valve when the brakes 
are released? 

A. The increase of brake-pipe pressure causes the pressure 
in cylinder h on the left of the piston to increase, forcing pis- 
ton, slide valve and graduating valve to the position shown in 
Fig. 21. Port r in the seat connects through port n in the 
slide valve, the cavity in the graduating valve, port m in the 
slide valve, with port p in the seat, the latter connecting with 
the exhaust. Thus brake-cylinder pressure can escape to the 
atmosphere. At the same time the auxiliary reservoir is re- 
charged through the feed groove % and through the quick- 
recharge ports y and ;. It is also helped to recharge by the 
volume of air which has been bottled up in the supplementary 
reservoir during the service application, which now connects 



74 Air-Brake Catechism 

through ports x and k with chamber E. In this wa}% the re- 
charging of the auxiliary reservoir is accomplished very 
quickly^ and constitutes the Quick-llecharge feature of the 
triple valve. 

Q. What is this position called? 

A. Eelease and Charging position. 

Q. How does the triple valve operate when a Gradu- 
ated Release is desired? 

A. Let us assume that the brakes were ajDplied by a 15- 
pound reduction^ or that brake-pipe pressure was reduced 
from 110 to 95 pounds. Eeferring to Fig. 23^ Service-Lap 
position; the pressure in cylinder h on the left of the piston 
is 95 pounds^ while that in chamber R and the auxiliary 
reservoir is slightly less^ say 9-1 pounds^ and the pressure 
in port X and the supplementary reservoir is still 110 pounds. 
To partally release the brakes the engineer partially reinstates 
brake-pipe pressure. We will say that he raises it from 95 
to 100 pounds. As soon as the pressure in cylinder h rises 
a little, it moves the piston, slide valve and graduating valve 
to the release position as shown in Fig. 21. The pressure in 
cylinder h is now 100 pounds the auxiliary-reservoir pressure 
feeds up through feed groove i and ports y, j and x to 100 
pounds. But the large volume of air in the supplementary 
reservoir is still only slightly below 110 pounds; it therefore 
tends to raise the pressure in chamber R above 100 pounds 
by air flowing in through port x. As soon as this pressure 
gets a little above 100 pounds, it moves the piston and grad- 
uating valve again to the left until the piston strikes the 
slide valve, as shown in Fig. 25. Feed groove i, ports j and x 
are now closed, preventing the auxiliary-reservoir pressure 
from rising any higher; at the same time port m is closed, 
which stops the exhaust of brake-cylinder air througli ports 
r^ n, m and p to the atmosphere; consequently only ii part 



. Type "L'' Tiiiple Yalve 75 

of the brake-cylinder air escapes^ and the pressure is corres- 
pondingly reduced^ but the remaining pressure is retained. 
This is the Graduated Release feature. 

Q. Can a second graduation in release be made? 

A. Yes; the process just described can be repeated until 
the brake-pipe pressure is raised to the normal amount^ and 
the brake-cylinder pressure completely released. 

Q. What is the position just described, and shown in 
Fig. 25 called? 

A. Eelease-Lap position. 

Q. What occurs in the triple valve in Emergency 
applications? 

A. The sudden reduction in brake-pipe pressure and cyl- 
inder h causes the piston^ slide valve and graduating valve 
to move to the left with such force as to compress graduating 
spring 22^ until the piston strikes the gasket at the end of 
the cylinder^ as shown in Fig. 26. In this position^ the slide 
valve uncovers port t in the seat and allows auxiliary-reser- 
voir pressure to flow to the top of emergency piston 8^ forcing 
it downward, thereby opening emergency valve 10, and allow- 
ing brake-pipe air to raise check valve 15 and flow rapidly 
through cavities Y and X to the brake cylinder. At the same 
time port s in the slide valve registers with port /• in the seat 
and permits auxiliary reservoir air to iiow to the brake cylin- 
der. AYhen the increasing brake-cylinder pressure and the de- 
creasing brake-pipe pressure become equal, check valve 15 is 
forced to its seat by the spring between it and the emergency 
valve^ so that no air can flow back from the brake-cylinder to 
the brake pipe. So far, the operation is the same as in the old 
standard quick-action triple valve. But with the L Triple 
other operations occur in emergency as follows : Port c, which 
leads to the left of the vent -valve piston 31, is connected by 
ports d and n in the slide valve with port r leading to the 
brake cylinder. In all other positions of the triple valve, 



■■^■■■■■■■I 



76 Aie-BfvAke Catechism 

port c is open to chamber E; the right side of vent-valve piston 
31 is always connected to chamber R; consequently at such 
times the vent-valve i^iston has equal pressures on both sides 
and vent v?lve 27 is held to its seat by the spring under it. 
But in emergency^ the chamber on the left of the vent-valve 
piston is connected to the brake cylinder as just described^ 
thereby relieving the pressure on the left^ and causing the 
pressure still remaining in the right to force the piston and 
vent-valve to the left^ as shown in Fig. 26. This opens the 
vent- valve and connects the supplementary reservoir to cham- 
ber Pv through port x and the vent valve. The result of this 
is that the volumes of both supplementary and auxiliary 
reservoirs are united and become equalized with the brake- 
cylinder, causing a much greater pressure of equalization than 
if the auxiliary reservoir alone was used. 

Q. With 110-pound brake-pipe pressure, what pressure 
of equalization is obtained in emergency in the brake 
cylinder with the L Triple Valve? 

A. Xearly 105 pounds. 

Q. With the ordinary high-speed brake, the high pres- 
sure equalization is reduced by a reducing valve ; is this 
also done with the L Triple Valve? 

A. No. Eef erring to Fig. 26, cavity q in the slide valve 
does not conect with port /• in emergency, so that the safety 
valve, connecting with port h is shut off from the brake cyl- 
inder. Consequently the high pressure is retained until the 
brake is released. 

Q. Why is this? 

A. Because emergency applications are for use only at 
times of danger^ or to save life, and at such times, the greatest 
stopping power possible is necessary^ regardless of everything 
else. The weights of cars are greater, and the speeds are 
higher than those common at the time that the high-speed re- 



Type "U' Triple Valve 77 

(lucing valve was introduced^ so that now with modern con- 
ditions, it is considered best to run the risk of sliding a few 
wheels^ if the result makes a considerably shorter stop. 

Q. Is the safety valve cut off from the brake cylinder 
at any other time? 

A. ISTo^ only in emergency applications. 

Q. In what positions of the triple valve does the vent 
valve operate? 

A. Only in emergency. 

Q. Does the vent valve remain open during the entire 
emergency application? 

A. No; as soon as the tw^o reservoirs and brake cjdinder 
become equalized^ the spring back of the vent forces it shut. 

Q. What would happen if the vent valve stuck open? 

A. Probably an emergency application w^ould occur for 
every application of the brakes, whether desired or not. At 
any rate, a much higher pressure of equalization would be 
obtained than desired. 

Q. What should be done in such cases? 

A. Eemove the cap nut from the vent- valve portion and 
examine the spring back of the vent valve. It is probably 
broken or weakened so as not to be able to force the vent 
valve to its seat. 

Q. If dirt gets on the seat of the safety valve, what 
will happen? 

A. The brake will gradually release in service applications^ 
accompanied by a blow at the safety valve. 

Q. Is any prevention made against dirt getting to the 
safety valve? 

A. Yes, an air strainer is placed in the passage to the 
safety valve from the slide valve. 



78 Aie-Brake Catechism 

Q. With this triple valve, is there any air strainer 
where the brake-pipe air enters the triple valve, as there 
is in the old standard quick-action triple? 

A. Yes, a h ranch-pipe air strainer is placed in the brake- 
pipe branch just where it connects with the cylinder pressure 
head. 

Q. Wliat diseases and troubles may be found in the 
L Triple Valve? 

A. Besides those just mentioned, the same troubles and 
cures may be applied to the L Triple as already described 
under the old standard quick-action triple valve. 



CHAPTER III. 

WESTINGHOUSE FREIGHT EQUIPMENT. 

Q. Name the different parts of the equipment. 

A. 3 (Fig. 27) is the piston sleeve and head, 9 the release 
spring, 4 the front cylinder head, 2 the cylinder body, A the 
leakage groove, 7 the packing leather, 8 the expander ring, 
G the follower plate which holds the packing leather 7 to its 
place, B the pipe connecting the triple valve and brake cyl- 
inder, and 15 the gasket which makes a tight joint between 
the anxiliary, triple, and pipe B leading to the brake cylinder. 

Q. Explain the use of the release spring 9 (Fig, 27). 

A. When the brake is applied, air is put into the cylinder 
2 through pipe B, and the piston 3 is forced to the left, com- 
pressing the release spring. When the air is released from the 
l)rake cylinder, the duty of the release spring is to force the 
piston to release position as shown in the illustration. 

Q. What enters the sleeve 3 (Fig. 27)? 

A. The push rod through which the braking power is 
transmitted to the brake rigging. 

Q. Of what use is the expander ring 8? 

A. iTo keep the flange of the packing leather 7 against 
the walls of the cylinder. The expander ring is a round 
spring. 

Q. Of what use is the packing leather 7? 

A. As air enters the brake cylinder, the flange of the pack- 
ing leather is forced against the walls of the cylinder, thus 
making a tight joint to prevent the passage of the air by the 
piston and out to the atmosphere through the open end of the 



80 



Air-Brake Catechism 




cylinclier ait the left. 
If the leather leaks^ 
the brake will leak off. 

Q. Of what use is 

tlie leakage groove 

A (Fig. 27)? 

A. . The piston as 
^ shown in the put is in 
w release position. If 

5 on a Ions: train there 

6 should be any leak in 
the brake pipe that 
would draw a triple 
piston out far enough 
to close the exhaust 
port in the slide valve^ 
and there were a leak 
into the brake cylin- 
der^ the pressure 
would gradually accu- 
mulate and force the 
piston out^ causing 
the shoes to drag on 
the wheels were it not 
for the leakage groove. 

This will allow any 
small leakage into the 
brake cylinder to pass 
through the groove 
and out of the other 
end of the cylinder to 
the atmosphere. 



H 
W 

o 

M 

w 

O 

W 
o 

h- 1 

H 

02 



t- 

C^ 



o 



Freight Equipment 81 

If the brake connections are taken up so short that the 
piston will not travel by the leakage groove when the brake is 
set, the air w411 blow past the piston through the groove and 
release the brake on this car. In this case^ were it not for 
the groove^ the wheels would be slid. 

Q. What is the duty of the pipe B? 

A. When the brake is applied, air passes from the auxil- 
iary reservoir through the triple and pipe B to the cylinder. 

When the brake is released, air passes from the cylinder 
through pipe B^ the triple exhaust port and out to the at- 
mosphere, or, if a retainer is used, it passes from the triple 
into the retainer pipe, which is screwed into the triple ex- 
haust, and out of the retainer according to the position of its 
handle. 

Q. Of what use is the auxiliary reservoir 10 (Fig. 27)? 

A. This is where the supply of air is stored with which 
to apply the brake on this one car. 

Q. What is the valve on top of the auxiliary? 

A. It is called the release valve. By lifting on the handle 
of this valve the pressure in the auxiliary reservoir 10 may 
be released. If this valve leaks, after the brake is applied, 
the reduction of auxiliary reservoir pressure thus made will 
release the brake. 

Q. What use has the plug 11? 

A. To drain off any accumulation of water in the auxiliary 
■leservoir. 

Q. What harm will ensue if gasket 15 leaks? 

A. The leak may be from the auxiliary reservoir to the 
atmosphere or from the auxiliary into pipe B leading to ihe 
jrake cylinder. After the brake was applied, the reduction 



82 Air-Brake Catechism 

oi auxiliary reservoir pressure caused by this leak would 
allow the brake-pipe pressure to force this triple to release 
position and release this brake. The leak would then draw 
air from the brake-pipe through the triple feed ports, making 
a brake-pipe reduction that with any other leaks on the train 
would help to creep on the other brakes. 

Q. Is the freight-car equipment diflferent from the air- 
brake equipment on the passenger car? 

A. It is smaller, but the principle of operation is the 
same. In a passenger equipment the pipe B does not run 
tlirough the auxiliary reservoir and the auxiliary and brake 
C3dinder are not fastened together. The appearance is dif- 
ferent, but aside from size, they are alike. 

Q. Why has the oil plug been removed from the brake 
cylinder? 

A. So that it will be necessary to take the cylinder apart to 
clean it. Pouring oil into the oil hole is responsible for the 
ruination of rubber seats in emergency valves. 

Q. Fig. 27 shows a standard equipment for freight 
cars ; are they ever furnished in any other form? 

A. Yes ; the space limitation on some cars forbids the use 
of the combined equipment illustrated in Fig. 27. In such 
cases, what is known as the detached equipment is used^ and 
the brake C3'linder and auxiliary reservoir are connected by a 
suitable pipe. 

In very exceptional cases two cylinders are used in connec- 
tion with one reservoir and one triple valve, but the principle 
of operation remains the same. Tlie usual piston stroke is 
twelve inches, but this is reduced to eight inches where twin 
cylinders are used, and in some special combined and detached 
equipments. 

Q. How many kinds of freight equipments are there 
and with what weight of car are they used? 



Piston Travel 83 

A. 8 and 10-incli equipments. The light weights of cars 
for which each is used are 22^000 to 37^000 for 8-inch, and. 
37,003 to 58,000 for 10-inch. 

PISTON TEAVEL. 

Q. What determines the amount of travel a piston will 
have? 

A. The slack in the brake rigging and any lost motion in 
the car brought out by the application of the brake. 

Q. How is the piston travel usually adjusted? 

A. By changing the position of tlie dead truck levers, 
unless an automatic slack-adjustment is used. 

Q. Which is called the dead lever of a truck? 

A. The one held stationary at the top with a pin. 

Q. What is the other lever on the truck called? 

A. The live lever. 

Q. What is the lever fastened to the piston usually 
called? 

A. The piston lever. 

Q. What is the corresponding lever at the other end 
of the cylinder in a passenger equipment called? 

A. The cylinder lever if connected to the cylinder. When 
connected to a fulcrum as in freight service, it is commonly 
called a floating lever. 

Q. Are these levers ever spoken of differently? 

A. Yes, sometimes both are referred to as cylinder levers. 

Q. In passenger equipment there is sometimes a lever 
between the cylinder levers and truck levers, one end of 
which is connected to the hand brake and the other to 
the live truck lever. What is this lever usually called? 

A. The Hodge, or floating lever; the latter name is the 
one more commonly used. 



84 Air-Brake Catechism 

Q. We have seen in studying the triple valve that a 
five-pound brake-pipe reduction caused the triple to allow 
air to expand into the brake cylinder from the auxiliary 
reservoir until its pressure was reduced five pounds. How 
much pressure does this give us in the brake cylinder? 

A. That depends upon the piston travel. It may be more 
or less than five pounds ; it might be five pounds. 

Q. Explain this answer. 

A. We notice that the auxiliary reservoir is much larger 
than the brake cylinder; the reservoir pressure is high, the 
brake cylinder has no pressure ; as tlie reservoir pressure falls, 
the brake cylinder pressure builds up; the amount that it 
builds up depends on the volume of the cylinder^ that is^ on 
the distance that the piston moves out ; but it must be remem- 
bered that a small part of the air put into the C3dinder goes 
through the leakage groove before the piston gets by and 
closes it. There is still another point. If no air were put 
into the brake cylinder and the piston were pulled out when 
the exhaust port was closed^ a vacuum would be formed. 
When the air enters the cylinder it must first fill this space 
to atmospheric pressure before a gage placed on the cylinder 
would begin to show any pressure. The longer the travel, 
the more air it would take to fill the space and the less pres- 
sure there would be for the five pounds reduction in the res- 
ervoir. 

Q. Which would give a higher pressure for a given 
reduction, long or short piston travel? 

A. Short travel. 

Q. Why? 

A. Because with a short travel the same amount of air 
would be expanded into a smaller space. 

Q. With the 8-inch freight equipment and old stand- 
ard triple valve, how much brake-cylinder pressure do we 



Piston Travel 



85 



get for a seven-pound brake-pipe reduction with a 6 and 
a 9-inch travel? 

A. Eeferring to the table we see that we get seventeen 
pounds with the 6-inch^ and eight pounds with the 9-inch 
travel. 





Piston Travel and Resultant Cylinder Pressure for 8-Inch 




Freight Equipment and Old 8ty]e Triple Valve. 


Brake Pipe 
Reduction. 






















4 


5 


6 


7 


8 


9 


10 


11 


7 


30 




17 


13 


10 


8 


j Piston not en- 
1 tirely out 


10 


50 


39 


31 


25 


20 


17 


14 


11 


13 


58 


56 


45 


37 


31 


27 


23 


19 


16 


•• 


-• 


54 


50 

52 


42 
50 


36 
44 


32 
41 


28 


19 


36 


22 


•• 




•• 


' ' 




49 


48 


44 


25 


47 



There are two spaces where it says "Piston not entirely out," 
where no brake-cylinder pressure is given for a seven-pftund 
brake-pipe reduction. This does not mean there was no pressure 
there, as there must have been or the piston could not have 
gone out and compressed the cylinder release spring. The or- 
dinary air gage does not register any pressure less than five 
pounds, and with a seven-pound brake-pipe reduction the pres- 
sure gotten in a ten- or eleven-inch piston travel is less than five 
pounds. 

Seventy pounds brake-pipe pressure was used in obtaining 
these figures. 

Q. With a sixteen-pound reduction? 

A. Fiftj^-four pounds with the 6-inch^ and thirtj^-six 
pounds with the 9-inch. 

Q. With a twenty-two-pound reduction? 

A. After the sixteen-pound reduction^ the brake did not 
set any harder on the 6-inch travel because the auxiliary and 
brake-cylinder pressures equalized at that pointy and this 
brake was fully set. With the 9-inch travel the air from the 
auxiliary reservoir had 4 inches more space into which to 
expand, and the brake was fully set when a twenty-one pound 



8G Aie-Brake Catechis:m 

reduction had been made^ gi^ig forty-nine pounds brake- 
cylinder pressure. 

Q. What does this show? 

A. That a brake with a short piston travel is more power- 
ful than one with a long travel ; tliat a brake with the auxil- 
iary reservoir and brake-cylinder pressures equalized cannot 
be applied any harder by a further reduction of brake-pipe 
pressure^ and that if piston travel varied in a long train^ be- 
tween 4 and 11 inches, there would be no uniformity in the 
braking power applied in the different parts of a train. 

Q. What difference in brake-cylinder pressure is ob- 
tained with the 8-inch freight equipment using the type 
*'K'' triple valve? 

A. For light brake-pipe reductions, a much higher brake- 
cylinder pressure is obtained with the type ''K^' triple valves ; 
while for full-service applications, there is very little differ- 
ence. Generally speaking, we obtain for a 5-pound brake- 
pipe reduction about three times as much cylinder pressure 
with the type "K^^ triple valve as with the old standard; for 
a 10-pound reduction, about 50 per cent, more pressure; for 
a 15-pound reduction, about 23 per cent, more pressure; and 
for a 20-pound reduction, there is practically no difference. 

Q. What brake-cylinder pressures are obtained with 
the 10-inch freight equipment, as compared with the 
8-inch? 

A. Practically the same, for the same brake-pipe reduc- 
tions. 

Q. With an 8-inch freight equipment and the old 
standard Westinghouse triple valve, at about what pres- 
sures do the brake-cylinder and auxiliary reservoirs be- 
come equalized when 70-pound brake-pipe pressure is 
used? 

A. 



4' 


5' 6' 


r 


8' 


9' 


10- 


11' 


piston travel 


58 


56 54 


52 


51 


49 


48 


47 


pounds 


13 


14 16 


18 


19 


21 


22 


2o 


brake-i^ipe reduction 



Piston Travel < 87 

Q. What would be the approximate brake-cylinder 
pressure, with the travel as given in the table, were the 
brakes set in emergency, using an 8-inch freight equip- 
ment. 

A. 4 in., 5 in.^ 6 in.^ 7 in. piston travel. 

62 61 59^ 58% emergency pressure. 

8 in.^ 9 in.,, 10 in. 11 in. piston travel. 
57% h^y2i ^^V2 55 emergency pressure. 
Q. Why do the brakes set harder with the quick-action 
triple in emergency than in service? 

A. Because in the emergency application the quick-action 
triples put air from both the auxiliary and brake pipe into the 
brake cylinder. 

Q. Can full emergency pressure be obtained after hav- 
ing made a light brake-pipe reduction in service applica- 
tion? 

A. Ko. 

Q. Can any gain be made? 

A. Yes, if the reduction has not been too great. By refer- 
ring to the table we see that a thirteen-pound reduction sets 
a 4-inch travel brake in full. If emergency were now used 
this brake would not set any harder, while we might gain a 
little on the long travel. With a given brake-pipe reduction, 
we would gain most on the car with the long travel^ but on 
neither would we get full emergency pressure. 

Q. Can a train be handled smoothly with uneven 
travel throughout the train? 

A. Not as smoothly as when the travel is more uniform. 
Q. What will be the effect with short travel at the 
head of the train and long at the rear? 

A. Having more braking power at the head would cause 
the slack to run ahead^, causing a jar. 



88 Air-Beake Catechism 

Q. What if the short travel were at the rear of the 
train? 

A. The tendencv would be for the slack to run back and 
break the train in two^ esj)ecially if the train were on a knoll. 

Q. How else would the piston travel affect the smooth- 
ness of the braking? 

A. In releasing the brakes. • 

Q. Suppose we had a train half of which had 4-inch 
travel and the other half 9-inch, which brakes would start 
releasing first if the engineer had made a ten-pound 
brake-pipe reduction and then, wishing to release the 
brakes, increased the brake-pipe pressure? 

A. They should all start about the same time^ biit the 
tendency is always for head brakes to start releasing first if 
the travel is about alike^ as the air enters the brake pipe 
from the main reservoir at the front of the train^ and the 
pressure is naturally a little higher here when recharging. 

Q. Is the same true after a thirteen-pound reduction? 
A. Yes. 

Q. After a twenty-two-pound reduction? 

A. Xo ; the long travel brakes will start releasing first. 

Q. Why? 

A. Kef erring to the table we see that the 4-inch travel was 

not applied any harder after a twelve-pound reduction had 
been made; but the 9-inch travel continued applying harder 
until a twenty-one pound reduction of brake-pipe pressure 
had been made. With the brakes fully set we have fifty-eight 
pounds pressure in the auxiliary reservoir and cylinder of the 
4-inch travel car and forty-nine on the long. Brake-pipe 
pressure has to overcome auxiliary reservoir pressure to force 
the triple pistons to release position, and it is easier to over- 
come forty-nine than fifty-eight pounds ; hence the triple pis- 



Piston Travel 89 

ton on the long travel car will go to release position with 
less of an increase of brake-pipe pressure than will the triple 
on the short travel car. 

Q. State the general rule in regard to this question. 

A. If reductions have not been continued after cars with 
the short piston travel have been fully set^ all brakes should 
start releasing about the same time; but if the reductions of 
brake-pipe pressure are continued after the short travel brakes 
are fully set^ an increase of brake-pipe pressure will start 
the long travel brakes releasing first. 

Q. If a long and a short travel brake are started re- 
leasing from the same pressure at the same time, which 
will get off first and why? 

A. The short travel^ because the piston has a shorter 
distance to go and there is a less volume of air to be gotten 
rid of through the exhaust port of the triple. 

Q. We have two cars with the same piston travel. 
What is the trouble if both are started releasing at the 
same time and one gets off quicker than the other? 

A. The release spring in one cylinder is weaker or the 
cylinder corroded. 

Q. What harm would it do to take a piston travel up 
to 2 inches. 

A. The piston could not get by the leakage groove^ and 
the brake would not stay set. 

Q. What harm would it do to let the travel out to 13 
inches? 

A. The piston would strike the head, and we would have 
no brake on that car. 

Q. Does having very long piston travel in a train re- 
quire any more work of a pump in descending grades? 



90 Air-Brake Catechism 

A. lYes ; the air has to be used more expansively, and the 
pump will have to supjDly more air in recharging. 

Q. If we try the piston travel on a car when standing, 
will we find it to be the same as when running? 
A. No. 
Q. Why not? 

A. For several reasons ; the shoes pull down farther on the 
wheels when running; the king bolts being loose allow the 
trucks to be pulled together; spring in brake beams, loose 
pins in jaws, loose brasses on journals, the give in old cars, 
and any lost motion that will throw slack into the brake 
rigging; all these will cause the piston travel while run- 
ning to be greater than that w^hile standing. 

Q. If the piston travel is adjusted when a car is loaded, 
v/ill it remain the same when the car is light? 

A. It will, if the brakes are hung from the sand plank, 
but most brakes are hung from the truck bolster or the sill 
of the car. When the car is loaded, the truck springs are 
compressed and the shoes set lower on the wheels. Wlien 
the car is unloaded, the truck springs raise the bolster and car 
body, thus raising the shoes so that there is less clearance be- 
tween the brake shoes and wheels. This shortens the piston 
travel, as the piston does not have to travel so far to bring 
the shoes up to the wheels. 

Q. How could you tell the piston travel on a car if it 
had no air in it? 

A. This can be told on freight cars where the hand brake 
and air brake move the push rod in the cylinder in the same 
direction when applying the brake. To tell the travel, shove 
the push rod into the cylinder until it bottoms. Make a mark 
on the push rod and set the hand brake. The distance the 
mark on the push rod has moved will be, approximately, the 
piston travel when using air. 



PisTOx Travel 91 

Q. How much variation is permissible? 

A. The smaller the amount of variation the better, but in 
road service it is the aim to keep piston travel between 5 and 

inches; on long heavy grades it is customary to have no 
travel exceed 6 inches. 

Q. Is there any device which will keep a constant pis- 
ton travel on a car without any outside aid? 

A. Yes^ a slack adjuster. 

Q. What slack adjuster is in most general use? 

A. The American Brake-Slack Adjuster. 

Q. Is this better than a hand adjustment? 

A. Yes, because it does its work when the car is in motion, 
and true travel is had because all lost motion is brought out 
at this time. 

Q. What is the most satisfactory travel for general 

use? 

A. Between 6 and 7 inches. 

Q. Where would a moderately long travel be consid- 
ered better than a short one? 

A. In a practically level country^ where with short travel 
and a large number of air cars in a train, the train might be 
slowed up or stopped with a light brake-pipe reduction^ thus 
ausing too frequent releases. 

Q. What harm would a too short travel do? 

A. The piston might not get by the leakage groove, and 
the shorter the travel the more danger of sliding the wheels 
on acount of the greater braking power developed. A too 
sliort travel does not give sufficient shoe clearance, and causes 
a train to pull hard if the brake shoes drag. 

Q, On most passenger cars piston travel can be taken 
up by winding up the hand brake a little, as the two 



92 Air-Brake Catechism 

brakes work in opposition to each other. Is this a good 
practice? 

A. No; it is the act of a lazy workman^ and is dangerous. 
Q. How is it dangerous? 

A. If the air brake is set quickly, it is likely to snap the 
brake chain^ and if a passenger had hold of a hand brake wheel 
when the brake was applied, if the dog were not caught^ 
the wheel flying round might break his hand or arm. 

Q. If the hand brake on a car works with the air, and 
the air brake was applied, what would result if the hand 
brake were then applied? 

A. The braking power developed would be too much for 
the safety of the wheels^ rods^ etc.^ since the resultant brak- 
ing power is equal to the sum of the power of both brakes. 

Q. If the air brake were then released what difficulty 
would be experienced? 

A. Since the hand brake retains all of the power of both 
brakes^ in this case it would be a very difficult matter for 
the brakeman to release the brake. 

Q. With this kind of a brake what would result if the 
hand brake were first applied and then the air? 

A. If the air brake were more powerful than the hand 
brake, slack would be thrown into the hand brake chain, and 
the gain in power would be the excess power of the air over 
that of the hand brake. If the air power were not as strong 
as that of the hand no effect would be produced since the 
pull in the hand brake rod would be diminished an amount 
equal to the power of the air. 

Q. If the hand and air worked opposite, that is, they 
tended to move the push rod in opposite directions to ap- 
ply the brake (see Fig. 108), what effect would be pro- 
duced if the air brake was applied and then the hand 
brake? 



Piston Travel 93 

A. Tlie air brake fully applied is usually stronger than 
the hand brake, hence the pull on the hand brake rod due to 
the air pressure would be greater than could be exerted by the 
brakeman, and the brake wheel could not be turned after the 
slack in the brake chain had been taken up. Under these 
conditions no braking power could be gained by using the 
hand brake. 

Q. If the hand brake were first applied and then the 
air what would be the result? 

A. Applying tlie hand brake too]^ up all the slack in the 
brake rigging and forced the push rod and piston in as far 
as they could go. When the air from the auxiliary reservoir 
passed through the triple valve to the brake cylinder it would 
pass through the leakage groove to the atmosphere and simply 
the power of the hand brake would remain. The clearance 
in the C3dinder being very small would result in a very high 
pressure when the air first entered, thus tending to strain 
the rods and brake-chain, but the air would quickly escape 
as explained. 

Q. Which is the better brake from the standpoint of 
danger to the brakemen? 

A. The one in which both work together. If. where the 
brakes work opposite, a man is using the hand brake at the 
same time the engineer uses the air, or an air hose bursts, the 
power will turn the brake-wheel in the opposite direction tend- 
ing to throw the brakeman from the train. 

Q. If the cars of a train are equipped with air and 
hand brakes working together, and the train was being 
controlled by air, what could be done if the engineer lost 
control of the train? 

A. The engineer could call for bralces and without releas- 
ing the air, the crew could add the power of the hand brakes 
to that of the air. 



94 Air-Bhake Cateohism 

Q. What would have to be done in a case like this if 
the hand and air brakes worked opposite? 

A. After calling for brakes it would be necessary for the 
engineer to make a release before the crew could apply the 
hand brakes^ since if this were not done and the hand brakes 
were applied^ any leakage of brake cylinder pressure 
would allow the piston to move in^ thus throwing slack into 
the brake rigging and releasing the hand brake. 

Q. How about leaving cars on a grade if the air brake 
is applied? 

A. If the hand and air work together^ the hand brake 
can be applied without first releasing the air and it will re- 
main set after the air leaks off. If the brakes work opposite, 
it is necessary to bleed the car before applying the hand 
brake ; if this is not done^ the release of the air brake by leak- 
age will also release the hand brake and the car will run away. 

To be on the safe side it is best, as a general rule, to al- 
ways release the air on one car at a time and apply the hand 
brake, when leaving a car or train on a grade ; but this would 
not be necessary, from the standpoint of safety, if all brakes 
worked together. 

Q. Are most brakes designed to work together or op- 
posite? 

A. A large majority of freight car brakes are designed to 
work together, while in passenger service the opposite is true; 
but the importance of this question will result eventually in 
practically all brakes being designed to work together. 

THE AMERICAN AUTOMATIC BRAKE-SLACK AD- 
JUSTER AND PISTON-TRAVEL REGULATOR. 

Q. Name the different parts of the American Brake 
Slack Adjuster shown in Fig. 29? 





Slack Adjuster 




95 




p^m 


r 






J 


/ N h 




M 
o 
< 

m 





A'^ 



'<^ 







^ 


H 


^ 


;^ 


w 


y 


p 


^ 




p^ 


5?^' 

^ 








w 


w 


<< 


<H 


< 


O 




^ 


o 




^ 




o 


rr 


1— 1 
H 




h- 1 




1-1 


^ 


Ph 




^ 


O 


<Jl 


H 




H 


»— 1 


05 


o 


^ 


W 




m 




q6 




<M 




6 




M 




fe 





96 AiR-BPtAKE Catechism 

A. The cylinder; tlie packing leather held in position 
by the expander ring and follower ; the pawl ; the pawl spring ; 
the piston spring; the cylinder head and casing; and the 
ratchet nut. 

Q. Name the parts shown in Fig. 28? 

A. 1 is the ratchet nut; 2, the cylinder; 3^ the C)dinder 
head and casing; 4^ the adjuster screw; a, the port which 
connects pipe b with the inside of the cylinder ; and h, a pipe 
connection from the slack adjuster cylinder with port a of 
the main cylinder. 

Q. What is the object of the lug a (Fig. 29)? 

A. As illustrated in Fig. 29, its object is to lift the pawl 
out of the ratchet nut when the adjuster piston is in release 
position. In the position shown the ratchet nut can be 
turned by hand to take up or let out slack when necessary, as 
when applying new brake shoes. 

Q. Explain the operation of the adjuster. 

A. In Fig. 29 it is shown both in the normal or release 
position, and as when applied. If there is sufficient slack in 
the brake rigging, so that the piston in the large cylinder 
(Fig. 28) uncovers port a when the brake is applied, cylinder 
pressure will pass through port a, pipe h, and into the slack- 
adjuster cylinder (Fig. 29). The piston will be forced out, 
compressing the piston spring. The movement of the piston 
disengages the pawl from lug a, and the pawl spring causes 
the pawl to engage in the teeth of the ratchet nut. 

When the brake is released and the piston in the brake 
cylinder is forced to release position by the release spring, 
port a is connected with the non-pressure end of the cylinder, 
hence tlie air in the slack adjuster cylinder passes tlirough 
pipe h (Fig. 28), port a, and out to the atmosphere through 
the non-pressure head. 

^Yhen the air is released from the slack adjuster cylinder 



Slack Adjuster 



97 



the piston spring forces the piston back and it in turn, 
through the pawl^ turns the ratchet nut which draws the 
screw away from the c}dinder. Lever 5 (Fig. 28) is fastened 
to a crosshead attached to the adjuster screw, hence the lever 
is moved correspondingly, the effect of which is to draw all 
the brake shoes nearer to the wheels. 




RELEASED 



APPLIED 



IG. 29.- 



Sectional End View of American Automatic Brake 
Slack Adjuster. 






98 AiPi-BuAKE Catechism 

Q. How does this shorten the piston travel? 

A. The shoes being nearer the wheels it will require a less 
movement of the piston to bring the shoes in contact with the 
wheels. 

Q. How many teeth does the pawl skip at each move- 
ment of the adjuster piston throughout its stroke, and 
what movement of the crosshead attached to lever 5 (Fig\ 
28) result? 

A. The pawl iisnally skips one tooth, engaging the second 
of the adjuster nut each tune. One operation of the adjuster 
moves the crosshead, connected to the lever^, 1-32 of an inch. 

Q. If the adjuster nut 1 (Fig. 28) is moved one turn, 
how far will the crosshead attached to the lever 5 be 
moved? 

A. One-quarter of an inch. 

Q. What is the object in having the crosshead move 
but 1-32 of an inch for each operation of the adjuster? 

A. ^Mien a car is in motion false travel is often produced 
owing to unevenness of the track and similar causes; if the 
adjuster should take up all this extra slack the piston travel 
would frequently be found too short. 

Q. What is the controlling factor in the amount of| 
piston travel to be permitted? 

A. The location of port a in the brake cylinder (Fig. 28). 
It is usually located to obtain an eis-ht-inch ^^runninsr'^ travel. 

Q. If the brake is applied when a car is at rest and the! 
piston travel were but six or six and one-half inches, 
would you decide that the adjuster was not working prop-| 
erly? 

A. ^0. 

Q. Explain the last answer? 

A. The slack adjuster adjusts the '^running^^ travel at| 
eiglit inches^ and as the ^"^running"^ is always greater than th( 



Slack Adjuster 99 

'^standing^^ travel^ we would expect to find the piston travel 
shorter when the car was at rest. 

Q. Would the *' standing'' travel be the same on all 
■cars? 

A. No; this depends upon the total leverage and lost 
notion. 

Q. Would the ''running'' travel be the same on all 
■cars? 

A. Yes. 

Q. To apply new shoes it is necessary to^increase the 
shoe clearance ; how is this done? 

A. By turning the ratchet nut 1 (Fig. 28) to the left. 

Q. After the new shoes are applied how may the piston 
iravel be shortened? 

A. By turning the adjuster nut to the right. 

Q. How should we proceed to apply a slack adjuster 
a car? 

A. Drill port a so that brake cylinder pressure can reach 
)ipe 1) after the cylinder piston has travelled eight inches and 
rect the parts and piping as shown in Fig. 28^ pipe h to be 
opper. The smaller part of port a (Fig. 30) is drilled with 

%-inch drill ; the part of the port into which pipe h connects 

drilled and tapped for i/^-inch pipe. After erecting^ test 
oints with soap suds. Next put on a new set of brake shoes 
nd adjust the piston travel by means of the dead levers, from 
ix to six and one-half inches. 

The length of the different rods should be such that the 
ead and live levers will have an inclination so that when 
le shoes are worn out they will have a corresponding inclina- , 
on in the opposite direction. 

Q. What is the standard length between centers of 
oles in the rod connecting the cylinder levers when using 
le slack adjuster? 



100 



Air-Brake Catechism 



A. 42 inches for middle connection. 

Q. What is invariably the cause of the piston travel 
being too short on a car equipped with an American 
Brake Slack Adjuster? 

A. Either some of the slack has been taken np by the ban. 
brake, or the position of the dead levers has been changed. 




.T 
i 






- J:^"~ ^^^^ J A/ OCR. 

^i- 8'cri//yo€/?.. 

_^f'-w''CYHNQ£R. 
. £^ -/JS'C YL lAIDCff. - 



.^jjL^j^'cyiif^^^^ 



p^f. 30 —Showing Proper Method of DRn.Li>'G Brake Cylindet 
'when: used with the American Automatic Brake Slac 

Adjuster. 
Q. What may occasion the piston travel to become t( 

long? . ^ . . 

A. Pipe fc may be obstructed, leaks may exist m pipe 
or the slack adjuster cylinder, or the packing leather. Tl 
car may have been running some time with the slack part 
taken up on the hand brake, a subsequent entire release 
which would introduce an amount of slack that it won 
require some time for the adjuster to take up. 



^1. 

■)' 



Slack Adjuster [101 

Q. Is there ever a time when, with the brake released, 
he rachet nut can not be turned? 

A. Yes; when the crosshead is at the end of its stroke. 

Q. Why can the rachet nut not be turned under these 
conditions? 

With the ratchet nut at the end of its stroke^ and the 
iston travelling beyond the limit, air will operate the slack 
dj lister piston^ causing the pawl to engage a tooth of the 
atchet nut;, in which position it will remain^, since, the cross- 
:ad being at the end of its stroke^, the adjuster screw can- 
lot be turned. 

Q. How can the pawl be disengaged? 

A. The adjuster is so designed that the adjuster screw 
hen at the end of its stroke is drawn against a set screw at 
le end of the adjusting nut (Fig. 28), as shown in the cut. 
lemoving this set screw permits of a further movement of 
le crosshead and the usual operation takes place, allowing 
le pawl to be disengaged. The adjuster nut may then be 
urned by hand, thus moving the crosshead nearer the large 
ylinder for the purpose of giving sufficient slack to permit 
f the application of new brake shoes. The set screw should 
Iways be replaced after the pawl has been liberated and the 
rosshead moved back. 

Q. How often should the slack adjuster cylinder be 
leaned and lubricated? 

A. About once in six months, every time the brake cylinder 
cleaned and oiled. 

PRESSURE RETAINING VALVES. 

Q. With what equipments is the retaining valve used? 

A. Throughout the country on freight cars, and on 
;ngines, tenders, and passenger cars in mountainous country. 



102 Air-Brake Catechism 

Q. Why do they not use it on passenger cars in hilly 
country? 

A. It is not necessary^ as the higher braking power used in 
passenger service is sufficient to run moderate hills with 
safety. 

Q. Where is it usually located? 

A. Usually at the end^ close to the brake standard on 
freight cars^ and at the end about on the level of the edge of 
the hood on passenger cars. 

Q. Where is it located on cars having vestibules? 

A. On the outside of the vestibule^ in which case a special 
valve is used, the handle of which extends within the vestibule 
(see Fig. 34). 

Q. To what is it connected? 

A. To the exhaust port of the triple by means of a %-inch 
or i/^-inch pipe. 

Q. What is its use? 

A. To retain pressure in the brake cylinder to steady the 
train, and keep its speed from increasing too rapidly while 
the engineer is recharging the auxiliary reservoirs. 

Q. How do the handles of all valves stand when not 
in use? 

A. Straight down. 

Q. How do they stand when in use? 

A. In the position shown in the cut (Fig. 31). 

Q. If the brake is not applied, can it be set by turn- 
ing up the retainer handle? 

A. Xo; the retainer can be used only to hold air in the 
brake cylinder that has already been put there. 

Q. Explain the passage of the air through the retainer 
when not in use. 



PuEssuRE Retaining Valves 



103 



A. With tlie retainer handle pointing down, as when not 
in use^ any air coming from the cylinder would pass through 
ports b, a, and out to the atmosphere through port e. 

Q. Explain the passage of air through the retainer 
when in use, as shown by the cut. 

A. When the engineer increases his brake-pipe pressure 
the triple assumes release position^ and the air passing from 




the brake cylinder has to pass out to the atmosphere through 
the retaining valve. With the retainer handle turned up, the 
air passes through ports h, a^ and h, until it strikes the 
weighted valve 20. Any pressure over fifteen pounds forces 
this valve from its seat and passes through the restricted port 
opening c to the atmosphere. When the pressure in the cylin- 
der is reduced to fifteen pounds, it is held back by the valve 
20, 



lOi Air-Brake Catechism 

Q. What is the size of the small end of port c? 

A. One-sixtenth of an inch in diameter. 

Q. Why is it made so small? 

A. To keep the brake cylinder pressure from escaping to 
the atmosphere too rapidly after valve 20 is lifted. 

Q. How long will it take the cylinder pressure to re- 
duce from fifty down to fifteen pounds through this re- 
tainer? 

A. About twenty or twenty-five seconds^ during Avhicli 
time the auxiliary reservoirs with an average length of train 
have become pretty well charged. 

Q. Have all retainers this restricted port c? 

A. ISTo ; in some old retainers there are two ports of ^y4'i^^l^ 
diameter each. 

Q. What is the valve shown in Fig. 32? 

A. This is the double-pressure retaining valve manufac- 
tured by the Westinghouse Company. It will retain either 15 
or 30 pounds pressure in the brake cylinder according to the 
position of the handle of the valve. It is spoken of as the 
15-30 retainer. 

Q. Explain its operation. 

A. Its operation is about the same as the 15-pound valve, 
that is, if the handle points down no pressure will be held 
in the cylinder when the triple assumes release position. 
\Yheji in a horizontal position it retains 15 pounds and when 
in a position midway between the horizontal and the vertical 
a pressure of 30 pounds is retained. 

It will be seen that the handle controls the lift pin 9, Fig. 
32, and the lift pin in turn controls the upper weight. When 
the handle stands in the horizontal position the upper weight 
is lifted and the small weight controls the pressure ; if in the 
mid positon the upper weight is not lifted and the combined 
weight of the small and large wciglit act against the cylinder 
pressure to retain it. The escape of air is as in the 15-pound 



Pressure Ketaining Valves 



105 



valve, that is, it escapes slowly to the atmosphere through the 
restricted port when the valve is in use. 

Q. What is the necessity for a valve which will hold 
either 15 or 30 pounds? 

A. It has been found that on the heavier grades and at 
speeds that the railroads wish to maintain, that the 15-ponnd 
valve is not sufficient to permit of a recharge being accom- 
plished without gradually losing pressure. The use of the 
30-pound position permits of greater safety, speed and greater 
tonnage. 




^ "N^ 



i PIPE lAP^ 



B-OW 

pressure: 



^^^"^ 



Fig. 32. — The Westinghouse Double-Pressuke Retainino Valve. 




106 Air-Brake Catechism 

Q. Will a retainer hold more pressure with a long or 
a short piston travel on a car? 

A. It holds the same pressure regardless of the travel. 
The Yolimie held is greater on the long travel car. 

Q. How do we test retainers? 

A. Have the engmeer apply the brakes^ and turn up the 
retainer handles. Then signal him to release^ and wait about 
half a minute^ after which walk along and turn down the 
handles. If a blow accompanies the turning down of the 
handles^ the retainer is working pro23erly^ otherwise the 
pressure has leaked away. 

Q. What troubles would make a retainer inoperative? 

A. A leak in the plug valve operated by the retainer 
handle; weight 20 (Fig. 31) being gone or dirt on its seat; a 
split pipe leading from the triple exhaust to the retainer; or 
a leak in the packing leather in the brake cylinder which 
would allow the air to escape to the atmosphere. 

Q. What could be the trouble with the retainer if, 
after the brake was applied and the retainer put in use, 
no air escaped from it when the engineer increased the 
brake-pipe pressure? 

A. Port c might be blocked. 

Q. If we wish to use a retainer in descending a grade, 
should the handle be turned up before or after the brakes 
are applied? 

A. It makes no difference^ if everything is in proper con- 
dition. 

Q. Explain a case where it would not be proper to 
turn up the retainer handle until just before we wish to 
use it. 

A. If the rubber-seated or the slide valve in the triple 
leaked, and we turned up the retainer handle^ air would ac- 
cumulate to a pressure of fifteen pounds in the cylinder if 



Pkessure Eetaixixg Valves 107 

the leakage groove were closed and set the brake on this car. 
If the train were just pulling over a summit^ the brake being 
on might stall the train. 

Q. How could we tell if it was safe to turn up a re- 
tainer handle before reaching* the top of a hill and not 
have the brakes drag? 

A. Put the hand over the exhaust port and hold it there 
a few seconds^ to see if any air is issuing; if not^ it is safe 
to turn up the handle. 

Q. Give a rule to produce best results in using the 
retainer. 

A. In testing retainers while standings turn up the handles 
at your convenience before or after the brakes are applied ; but 
using them on the road, turn them up after the brakes are 
applied or a short time before wishing to us them. 

Q. Is a retainer ever used except to steady a train 
when recharging? 

A. Yes; when brakes have been applied too hard, a few 
are sometimes used to keep the slack bunched after releasing, 
when drifting along preparatory to making a stop. 

Q. Set a brake with the full service application, then 
turn up the retainer handle, release and recharge. After 
charging the auxiliary in full again, make a full service 
reduction. Will the brake set any harder one time than 
another? 

A. Yes, it will set harder the second time. 

Q. Why? 

A. When we started to apply the brakes the first time, 
we had sevent}^ pounds auxiliary reservoir jDressure and 
nothing in the brake cylinder. The second time we had 
seventy in the auxiliary and fifteen pounds in the brake cyl- 
inder. By comparison we see that we had more air the 



108 Air-Brake Catechism 

second time with which to do our brakings and the pressures 
will therefore equalize higher. 

Q. Would we gain more the second time over that of 
the first with a long or a short piston travel? 

A With the long, because the retaining valve on the long 
travel car retains the same number of pounds in the cylinder 
as on the short one, but a larger volume; having a greater 
volume the pressures equalize correspondingly higher. 

Q. Do we gain the whole fifteen pounds more the sec- 
ond time over what is obtained the first? 

A. Xo ; we gain from about three to six pounds pressure, 
according to the piston travel. 

Q. About how much pressure do we get in the brake 
cylinder for a five-pound brake-pipe reduction? 

A. It varies from seven to eleven pounds with average 
piston travel. It may be more or less, but this would be a 
fair averao:e. 

Q. After getting the use of the fifteen pounds that the 
retainer holds, how much pressure would we then get in 
the cylinder for a five-pound brake-pipe reduction with 
an average piston travel? 

A. Between thirty and forty pounds. 

Q. Where a twenty-pound reduction will set a brake 
in full without the aid of the retainer, how much reduc- 
tion is necessary with the fifteen pounds it holds to aid? 

A. From twelve to fifteen pounds with fair travel^ and 
old style Xew York or Westinghouse triples about 15 pounds 
with the quick-service triple. 

Q. Name another gain after obtaining the use of the 
retainer. 

A. If we have to apply the brakes in full, it does not 
take so long to recharge, as the auxiliary and brake cylinder 
pressures equalize higher vvith the retainer to aid. 



Table 109 



(1) 


(2) 


(3) 


(4) 


(5) 


(C) 


(T) 






5 












•3 


'o 




'S ,. 


'£s 


£gS 




?^ 


% 


>, 




^.s 


<^-23 


S 


8l 


^ 
H 


o 


fl 

§3 


w 


^B 


1 


£■3 


o 


§" 


tf)0 


§1 
oP5 


Ih 




*« 


c« 


a 


a 


Oh"^ 


fi. ^ 


3 


9 


P^ 


H 


p^ 


10 


iO 


^ 


&H 


Qches. 


Poands. 


Pounds. 


Pounds. 


Pounds. 


Pounds. 


Pounds 


4 


62 


65 


23 


59 


571/2 


61 


5 


61 


63 


191/2 


55 


551/2 


59 


6 


591/2 


63 


131/2 


51 


53 


58 


7 


581/2 


63 


1114 


43 


53 


57 


8 


571/2 


63 


10 


38 


501/2 


56 


9 


5G1/2 


611/2 


8 


35 


48 


'55 


10 


551/2 


61 


— 


33 


46 


54 


11 


55 


60 


+ 


30 


45 


53 



The above figures were obtained by taking an average of four 
tests for each condition, using old style Westinghouse triple 
valves. 

Each test was made with a brake pipe and auxiliary reservoir 
pressure of seventy pounds. 

The first column represents the piston travel. 

The second column represents the brake-cylinder pressure ob- 
tained in emergency. 

The third column represents the brake-cylinder pressure ob- 
tained in emergency after the retainer has been used; that is, 
there was already a pressure of fifteen pounds in the brake-cylin- 
der held by the retainer when the emergency was used. These 
figures would be the same for either the old style or quick-service 
Westinghouse triple valves. 

The fourth column represents the brake-cylinder pressure ob- 
tained with a five-pound service reduction. 

The fifth column represents the brake-cylinder pressure ob- 
tained with a five-pound service reduction after once obtaining 
the use of the air held in the cylinder by the use of the retainer. 

The sixth column represents the brake-cylinder pressure ob- 
tained with a full service reduction. 

The seventh column represents the brake-cylinder pressure ob- 
tained with a full service reduction after getting the use of the 
retainer. 

+ simply means that the gauge used registered no pressure less 
than five pounds. With an 11-inch travel the air is expanded 
into so large a space that a very small pressure is obtained. 

The table should be read from the left to the right. 



110 



Aik-Brake Catechism 




RETAINING POSITION 




Fig. 33. — Retaixi>'g Valve used p:ig. 34. — ^^Pullmax Retaixixg 
WITH 12, 14 AND 16-iNcn Brake Valve, used ox Vestibule 
Cylixders. Cars. 





Fig. 35. — Staxdard Rf.tatxixg 
Valve used with 6. 8 axd 10- 
ixcH Brake Cylinders. 



Fig. 36.^Driver-brake 
Retaixixg 
Valve. 



Pressure Eetaixixg Valves 111 

Q. What are the retaining valves shown in Figs. 33, 
34, 35, and 36? 

A. Figs. 33 and 34 represent valves designed to operate 
with 12, 1-1 and 16-inch cylinders. Thongli slightly dif- 
ferent in structure, the operation is practically the same as 
the one already described. 

Q. Why is it necessary to have two sets of retaining 
valves for use with 6, 8, and 10 ; and 12, 14, and 16-inch 
cylinders? 

A. It is essential in releasing brakes that the pressure in 
all cylinders be reduced about alike. The ports in the valves 
for use with 12, 14 and 16-inch cylinders are correspondingly 
larger than those in the valves for use with the smaller cyl- 
inders. 

Q. What is the purpose of the extension handle (Pig. 
34)? 

A. This valve is for use on vestibule cars. The body of 
the valve is located outside the vestibule, but the handle ex- 
tends within. 

Q. What is the common name for this valve? 

A. The 'TuUman Eetaining Yalve.^' 

Q. What is the difference between this valve and the 
corresponding one for use on cars not equipped with vesti- 
bules? 

A. The keys are set at right angles to each other in the 
bodies of the two valves and, as already explained, the 'Tull- 
man" valve has an extension handle. 

Q. Is the operation of the two and the results accom- 
plished the same? 

A. Yes. 

Q. How many kinds of retaining valves are furnished 
by the Westinghouse Company, and what is their use? 



112 Air-Brake Catechism 

A. Five. The one shown in Fig. 35 is for use with 6, 8, 
and 10-inch cylinders on non- vestibule cars; practically the 
same valve^ but with an extension handle and key at right 
angles^ is used on vestibule cars. Figs. 33 and 34 represent 
the corresponding valves for use with 12, 14, and 16-inch 
cylinders. Fig. 36 is a cut of the Driver-Brake Eetaining 
Valve. 

Q. How does the Driver-Brake Retaining Valve oper- 
ate? 

A. In the same general way as the other, except that, if 
so desired, it may be placed on lap, as indicated, in which 
position no air can escape from the brake-cylinder. When the 
handle points straight up the usual 15 pounds is retained, 
when the triple piston is forced to release position. 

Q. For what special use was the Driver-Brake Retain- 
ing Valve designed? 

A. For use on freight engines and those hauling long 
passenger or excursion trains. It furnishes a means, within 
the control of the engineer, by which the slack of a train may 
be kept bunched, if desired^ when drifting up to a water crane, 
releasing brakes at slow speeds, and under similar conditions. 
This, of course, is not necesary when the engine is equipped 
with straight air. 



fc:" 




Fig. 36 a. Nine and One-half Inch Pump. 



CHAPTEE IV. 

WESTINGHOUSE AIR PUMPS 

Q. What sizes of pumps are there? 

A. The 8, 9^^ 11, and S^/^-inch cross compound. 

Q. What is the use of the pump in the air-brake sys- 
tem? 

A. To compress the air used in applying and releasing 
the brakes. 

Q. Which pump has been mostly used and why? 

A. Two 9%-inch pumps, because the number of air cars 
now used in trains requires a greater capacity to insure re- 
charging the train more quickly in descending grades. The 
use of two pumps also does away with an engine failure if 
one pump should fail. 

Q. How is dry steam obtained for the pump? 

A. A pipe is screwed into the dome near its top and a 
pump throttle conveniently located in the pipe, or a dry 
pipe is run from the top of the dome back through the 
boiler and coupled to a pump throttle screwed into the top 
of the boiler inside of the cab. Steam is also taken from a 
fountain^' conveniently located. 

Q. What would happen if this dry pipe leaked inside 
the boiler? 

A. Water would work into the pump and wash out the^oil, 
causing the pump to groan and cut. 



114 



Air-Brake Catechism 



losv. nn 



nn ^1 09 

F " ^^,^— _... =^y— 1 1 




[EXHAUST 

iy2"PlPE 



1^2 "pipe 



112-tU 



Fig. 37. — Westixghouse 9V>-ixch Air Pump. 



9|/2-I^'GH Pump 



115 




Fig. 37. — Westinghouse 9i^-inch Aik Pump. 



116 Air-Brake Catechism 

Q. What is placed between the pump throttle and the 
pump? 

A. The lubricator and jDunip governor. 

Q. How are they located? 

A. The pump governor next to the pump, and the lubri- 
cator between the governor and pump throttle. 

Q. What would happen if the lubricator were placed 
next the pump? 

A. When the pump governor shut off the steam., with 
the lubricator ordinarily used, the steam between the lubri- 
cator and pump governor condensing would form a vacuimi 
that would draw all the oil from the lubricator, and there 
would be a great waste of oil. 

91^4-IXCH PUMP. 

Q. What is the office of the parts in the top head of 
the gi/s-inch pump (Fig. 37)? 

A. They with the reversing rod 71 form the steam valve 
motion of the pump. 

Q. What is Fig. 37? 

A. Two views of the 9%-inch pump showing the steam 
and air pistons and rod, and the valve motion in the top 
head. 

Q. What are ports b, d, and c (Fig. 37) ? 

A. They correspond exactly to the ports in the valve seat 
of a locomotive. 

In Fig. 37, we see that h leads to the bottom of the steam 
cylinder, c' to the top, and d leads to tlie exhaust pipe at Y, 

Q. Of what use is port t (Fig. 37)? 

A. It is a port by means of which chamber E at the left 
of the small piston 79 is connected with the atmosphere 
through port d. 



9%.Inch Pump 117 

Q. If this port were not there, would the pump re- 
verse? 

A. No; when the main valve pistons 77 and 79 moved 
to the left^ a back pressure would be formed in chamber E 
that would stop the reversing movement of the pistons 77 and 
79 and stop the pmnp. 

Q. Explain the passage of steam after it enters the 
pump at X and its effect. 

A. Steam coming from the boiler through the pump gov- 
ernor enters the pump at X, thence passes through ports a^ a 
and a (Fig. 37)^ into chamber A between the main valve 
pistons. The area of piston 77 being so much greater than 
that of 79^ the steam moves these pistons to the rights carry- 
ing the slide valve 83 with them to the position shown in Fig. 
37. Steam in chamber A is noAV free to pass through ports 6^ 
V and &^ underneath the main piston 65. 

Q. What would become of any steam above piston 65? 

A. Any steam above this piston is free to pass to the at- 
mosphere through ports c, c\ the exhaust cavity B of the slide 
valve, dy d\ d"^, and through the exhaust pipe from Y, 

Q. How is the pump reversed? 

A. The main piston 65 is now being forced up by the 
steam pressure^ and just before it reaches the top of its stroke 
the reversing plate 69 strikes the lug j on the reversing rod 
71^ lifting the rod. As this rod is lifted the reversing slide 
valve 72 is carried up with it, and the pump is reversed. 

Q. What is the duty of the reversing slide valve 72? 

A. The duty of this valve is to admit and exhaust steam 
from chamber D between the piston 77 and head 84, and, as 
now shown, it exhausts steam from cavity D through ports 
h and h\ port H of the reversing slide valve, and through 
ports f, f\ d, d\ d^, and out at Y. 



118 Air-Brake Catechism 

Q. How does raising the reversing slide valve reverse 
the motion of the pump? 

A. As the reversing valve is lifted by the rod 71, port 
g in the bushing is exposed to the steam pressure which is al- 
ways in chamber C, which is in constant communication with 
chamber A by means of ports e and e . 

When valve 72 is raised^ steam passes through port g into 
cavity D. We now^ have equal steam pressure on both sides 
of piston 77, and it is balanced; but the pressure acting on 
the right of piston 79 moves the pistons and the slide valve 
to the left connecting the steam pressure in chamber A with 
the top of piston 65 through ports c and c and the under 
side of piston 65 is connected with the atmosphere through 
ports V^ b\ &, cavity B of the slide valve 83, d^ d\ d^, and 
out at Y. 

Q. The piston 65 is now on its down stroke; what 
brings the stroke to the point from which we started? 

A. The reversing plate 69 strikes the button at the bot- 
tom of the reversing rod 71 and pulls the reversing slide valve 
7^ down to its position as shown in Fig. 37. We have now 
completed one entire stroke of the pump. 

Q. Which are the receiving valves? 

A. Those marked 86 at the left of the air cylinder. 

Q. Which are the discharge valves? 

A. Those marked 86 at the right of the pump. 

Q. Describe the action of the air end of the pump. 

A. As piston 66 is raised, the air above the piston is 
compressed and a vacuum would be formed underneatli 
if air from the atmosphere did not enter through the lower 
receiving valve 86. 

The ports are so arranged that the pressure above the pis- 
ton will strike the receiving valve from above^ forcing it 
to its seat, and the discharge valve underneath, forcing it 



91/2-I^^CH Pump 119 

from its seat^ allowing the compressed air to pass down and 
out into the main reservoir at Z. 

The suction underneath the piston allows atmospheric 
pressure entering at ^N to force the low^er receiving valve 
from its seat and fill the cylinder underneath the piston with 
air. The lower discharge valve 86 is held to its seat by main 
reservoir pressure. When the pimip is reversed^ the opposite 
valves from those just described are affected in the same way. 

Q. Of what use is the port in the cap 74 which leads 
to the top of the stem 71? 

A. This port is connected with the top end of the steam 
cylinder. Were it not for this port there w^ould be a back 
pressure on top of stem 71 which would not allow the revers- 
ing slide valve to be raised to reverse the pump. This port 
is connected with the atmosphere through the top end of the 
steam cylinder, each time this end of the cylinder is connected 
with the atmosphere. 

Q. What is the capacity of a 9V^-inch pump in good 
condition? 

A. With one hundred and forty pounds of steam pressure, 
a 91/2-inch pump will compress air from zero to seventy 
pounds in about thirty-eight seconds in a reservoir 26% x 
34 inches, and from twenty to seventy pounds in about twen- 
ty-seven seconds. When operating at one hundred and twen- 
ty single strokes per minute, it should deliver about .twenty- 
eight cubic feet of free air per minute against ninety pounds 
air pressure. 

9%-Inch Pump — Peculiarities, Troubles, Care. 

Q. What should be done in packing the pump? 

A. It should be packed loosely and the gland nuts 96 
screwed up only sufficient to prevent a blow. Do not use a 



120 Air-Brake Catechism 

wrench if no blow exists when the gland is screwed up by 
hand. 

Q. Should asbestos or anything containing much rub- 
ber be used in packing a pump? 

A. Xo; asbestos hardens and is hard to remove, and rub- 
ber is likely to wear the stem too much. 

Q. How often should the air end of the pump be oiled? 

A. Modern practice demands that a pmnp in freight and 
passenger service should be oiled according to the work which 
they perform. The old method of oiling a pump only when 
it groans has been abandoned. 

Q. Some pumps have been run without ever 
oiling the air end ; how did the lower cylinder receive its 
lubrication? 

A. From the swab which should always be placed on 
the piston rod, and from the oily condensation that follows 
down the rod. 

Q. What kind of oil should be used in the air end of 
the pump? 

A. A good quality of valve oil gives the best results. The 
same oil that is used in the steam cylinder also gives best 
results in the air cylinder. 

Q. What care should be taken in starting a pump? 

A. It should be started slowly so as to get a pressure of 
twenty or thirty pounds for the air piston to cushion upon, 
and the condensed steam should be gotten rid of before the 
pump attains any speed. Get the lubricator at work as soon 
as the pump is started. 

Q. Does any harm result from oiling the air end of the 
pump through the suction? 

A. Yes; the suction holes are stopped uj), the air valves 
gummed, and a generally dirty and ineffective pump results. 



91/>-Inch Pump 121 

Q. What trouble will cause the pump to blow? 

A. Packing rings in the main steam and reversing pis- 
tons leaking^ slide valve 83^ or a leaky reversing slide valve 
72 are the main troubles. 

Q. What will cause a pump to pound? 

A. It will pound if it is not fastened firmly^ if the air 
valves are stnck^ or if there is too great a lift of air valves. 
Sometimes it will pound if the reversing plate is worn too 
much to reverse the pump quickly enough^ or if the nuts be- 
low the air piston are loose. 

Q. What would be the effect if the top discharge valve 
were stuck open? 

A. Main-reservoir pressure would always be on top of the 
air piston; this would cause a slow up-stroke and a quick 
down-stroke of the pump. No air would be drawn into the 
pump on the down-stroke. If the oil cock were opened on 
the pump, there would be a constant blow at that point as 
long as there was any pressure in the main reservoir, and 
no oil could be put into the air cylinder^ as it would be 
blown out by the escaping air. 

Q. What would be the effect if the bottom discharge 
valve were stuck open? 

A. The same effect as above described^ only on the oj^posite 
stroke of the pump. In this case the oil cock would not tel] 
us anything. 

Q. What would be the effect if the top discharge valve 
were stuck shut? 

A. The pump would have a slow up-stroke^ and unless the 
valve were forced from its seat^ would stop or go slow enough 
to allow the pressure above the air piston to leak by the 
packmg rings when the air pressure above the piston became 
as high as the steam pressure. 



122 Air-Brake Catechism 

Q. What would be the effect if the bottom discharge 
valve were stuck shut? 

A. The same effect as just described^ but on the opposite 
stroke. 

Q. What effect would follow if the top receiving valve 
were stuck open? 

A. Air would be drawn into the pump on the down-strol^e 
and forced back through the inlet port to the bottom of the 
air cylinder on the up-stroke. By placing the hand on the 
air inlet and watching the piston this trouble may be easily 
located. The pump would have a tendency to work faster 
on the up-stroke. 

Q. What effect would follow if the bottom receiving 
valve were stuck open? 

A. The same as just described, but on the opposite stroke, 

Q. What would be the effect were the top receiving 
valve stuck shut? 

A. No air would be drawn into the pump on its down- 
stroke, and a partial vacuum being formed above the piston 
would cause the pump to have a slower down-stroke, as the 
vacuum would be working against the steam, and a faster 
up-stroke, as the vacuum would be working with the steam. 

Q. What would be the effect if the bottom receiving 
valve were stuck to its seat? 

A. The same as with the top receiving valve stuck shut, 
but on the opposite stroke. 

Q. How may a stuck valve usually be loosened? 

A. By tapping the valve cage lightly. 
Q. How will a pump work with dirt on the seat of a 
discharge valve? 

A. The same as with a stuck receiving valve. The dirt 
on the valve allows main-reservoir pressure to feed back into 



9y2-lNCH Pump 123 

the pump and aid the steam on half the stroke^ causing one 
stroke to be quick, and work against tlie steam on tlie other 
stroke, causing the j)ump to work slow. 

Q. How could we tell that a receiving valve was stuck 
shut, or a discharge valve open, aside from the erratic 
action of the pump? 

A. The hand placed on the strainer would feel no air 
drawn in on one-half of the stroke. 

Q. How can we tell if the top discharge valve has a 
poor seat? 

A. Open the cock 98 (Fig. 37) and air will issue thence 
constantly if the dirt on the seat of the valve allows main- 
reservoir pressure to feed back into the cylinder. 

Q. What caused some of the first 9y2-inch pumps to 
stop? 

A. The port g did not extend quite far enough^ and the 
wear of piston 77 would sometimes allow it to travel far 
enough to close port g entirely, and the pump could not be re- 
versed. 

Q. How may a pump often be started if it stops? 

A. By jarring lightly on the top head. 

Q. At what speed are good results obtained from a 
pump? 

A. From forty-five to sixty double strokes a minute on 
a level, but in handling air trains on a grade this speed 
should be increased according to work to be done. 

Q. Why is it best not to run a pump too slow? 

A.. A pump running too slow will allow the air that is 
being compressed to leak by the packing rings 67 and air will 
not be drawn in at the other end of the cylinder as it should. 

With sixty strokes to the minute, a pump will make more 
air than with the same number of strokes spread over three 



124: Air-Brake Catechism 

minutes. In the latter case the compressed air has too much 
time to leak by the air piston-packing rings. 

Q. How can we tell if the prxking rings in a pump are 
loose? 

A. Have the pump working at fair speed and put the 
hand on tlie air inlet to see if the air is drawn in full stroke. 
Try this on both strokes, and if air is drawn in only during 
a part of each stroke^ the rings are loose. 

Q. What lift should the receiving and discharge valves 
have? 

A. 3/32 of an inch. 

Q. What will cause a pump to heat? 

A. Too small lift of air valves^ racing a pump^ loose air 
piston-packing rings^ using a small main reservoir on long 
trains, packing the piston rod too tight, or using so much 
oil on the air end of the pum|) that the pi]3e leading from the 
pump to the main reservoir is partly closed by the oil being 
baked to it. The pipe gradually becomes so small, that the 
friction caused by the air being forced through it causes the 
air to heat. This heat spreads to the pump. 

Q. What should be done to cool a hot pump? 

A. Ease up on the speed, when possible, if running fast, 
remove cap 7-1, and pour a small amount of good oil into the 
pump. 

Q. If the packing burns out of a pump, can it still com- 
press air? 

A. Yes; the lower half of the air cylinder will not be af- 
fected. 

Q. Does compressing air cause it to heat? 

A. Yes; the higher the pressure the greater the degree 
of heat, because of the friction due to forcing the air particles 
closer together. 



9y2-IxcH PCMP 125 

Q. What is likely to be the trouble if a pump dances? 

A. A leak on the seat of the reversing slide valve or a 
bent reversing stem ; also a burr being worn on the reversing 
plate^ thns allowing the button on the stem to catch. Too 
much lubrication has also been known to cause the reversing 
valve to fall and the pump to reverse. 

Q. How should a pump be located? 

A. It should be where the engineer will notice it if it 
stops. Under no consideration should it be located lower 
than the main reservoir^ as dirt and water would stay in the 
pump. 

Q. How may a pump be cleaned? 

A. By allowing a solution of lye in hot water to work 
through the pump. The pump should be worked slowly and 
the water caught in a pail before it enters the main reser- 
voir. Eun the solution through several times ; then run clean 
hot water through to wash out the lye^ or it will eat the 
leather gaskets throughout the brake system. 

Q. Where does the exhaust pipe connected to the pump 
at Y lead? 

A. Usually to the smoke box in the engine^ but this prac- 
tice is gradually giving way to the better one of running the 
exhaust pipe into the exhaust passage from the main cylinder 
to the stack. This latter method almost does away wifh the 
draught on the fire caused by the pump exhaust thus saving 
fuel, and the pump makes very little noise in working. Some 
engines are piped to carry the pump exhaust up over the cab, 
but this is awkward, noisy, and keeps the cab dirty. 

Q. What eflfect would be produced if the gasket under 
the top head leaked? 

A. If the leak were between the two ports, one leading 
to the top and the other to the bottom of the main piston, 
the pump would stop. 



126 Atr-Brake Catechism 

The accompanying talkie shows heat due to compression. 
This heat depends upon the initial temperature. The rise 
in temperature is due to the heat of compression. 



per 


ature of 


air 


before 


compression 






60° 


90° 


cc 


<•* 


a 


comjDressed 


to 


15 


lbs. 


177° 


212° 


a 




(.(. 






iC 


30 


'• 


255° 


294° 


cc 




u 






^' 


45 


a 


317° 


362° 


C6 




Ci. 






iC 


60 


u 


369° 


417° 


a 




a 






a 


75 


'•' 


416° 


465° 


cc 




iC 






cc 


90 


a 


455° 


507° 


a 




(.(, 






cc 


105 


^i 


490° 


545° 


Ci. 




cc 






cc 


120 


u 


524° 


580° 



Westinghouse ''Eight and Left-Hand'^ ?^ine and One- 
Half Inch Pump. 

Q. What is the difference between the nine and one- 
half inch pump shown in Fig. 38 and the one shown in 
Fig. 37. 

A. The operation of tlie two pumps is exactly the same; 
the parts are identical with the exception of the steam and 
exhaust connections^ and the drain cock put in to drain any 
accumulation in port A. 

Q. How do the steam and exhaust connections differ. 

A. Both are extended through to the other side of the 
pump for convenience in piping in case it is desirable to locate 
the pump on the left side of the engine. 

Q. Explain the proper use of the connections as shown 
in Fig. 38. 

A. 4 is the steam inlet and B the steam exhaust. 

Q. What must be done if this pump should be changed 
to the right side of the engine? 



9%-IxcTT Pump 



127 



A. Remove plug at C and fittings at A and excliange 
them; the same should be done with the ping at D and fit- 
tings at B. C will then be the steam inlet and B the steam 
exhaust. 




Fig. 38. — Right and Left-hand Pump. 



128 Air-Brake Catechism 

Q. Is there any difference in the air cylinder on a right 
and left hand pump? 

A. Usually none^ but sometimes an air cylinder is fur- 
nished with admission and discharge connections on each side, 
similar to the steam cylinder, so that the connections may be 
charged in the same way. 

Q. Explain the operation of this pump. 

A. A description of the operation of this pump would be 
but a repetition of what is said in the chapter concerning the 
standard nine and one-half inch pump. 

Elevex-Inch Pump. 

Q. What are the dimensions of cylinders and the 
stroke of the eleven-inch as compared with the nine and 
one-half inch pump? 

A. The nine and one-half inch pump is 9^2" ^ 9%" x 
10" stroke, as compared with 11" x 11" x 12" stroke with the 
eleven-inch pump. 

Q. What are the comparative capacities of the two 
pumps? 

A. With a piston speed of 100 feet per minute (which 
means 100 single strokes per minute for this pump), and 
operating continuously, the capacity of the eleven-inch pump 
is about 60 per cent, greater than the nine and one-half inch 
pump ; under the above conditions the larger pump will com- 
press 45 cubic feet of free air while the nine and one-half inch 
pump compresses 28 cubic feet, against ninety pounds air 
pressure in both cases. These figures, however, are fo. a 
moderate pump speedy and these capacities can, if desired, 
be exceeded, but in the same proportion. 

Q. Explain the operation of the eleven-inch pump. 

A. Although some of the parts are slightly different in 



Ceoss-Compound Pump 129 

construction^ the operation is the same as that of the nine 
and one-half inch pump described in the chapter beginning 
on page. 113. 

Q. Two sets of plugs are shown on either side of the 
steam cylinder ; of what use are they? 

A. These plugs are for convenience in piping the pump. 
The li/^-inch pings are at opposite ends of the same steam 
port. The 2-inch pings are at opposite ends of the exhaust 
port. The openings are used according to which side of the 
engine the pumps are located^ and provide a means of mak- 
ing the piping simple^ since a steam port opening is toward 
the cab and an exha.ust opening toward the front end^ if 
placed on either the engineer's or fireman's side. 

Q. Do the nine and one-half inch pumps have this pro- 
vision? 

A. The one usually placed on the engineer's side^ and 
known as the Eight-Hand Pump, does not, while the Eight 
and Left-Hand Pump, which may be used on either side, 
does. 

The 81/2-Inch Cross-Compound Pump. 

Q. Why are larger air compressors necessary in mod- 
ern railway service? 

A. Because of the increased size and weight of locomo- 
tives and cars, requiring larger brake equipment, and of the 
increased number of cars hauled in single trains. 

Q. What is the type of air pump shown in Fig. 39? 

A. It is called the 8i/2-inch cross-compound pump, and 
the drawing illustrates its exterior. 

Q. How many cylinders has the cross-compound pump, 
and what are they called? 

A. It has four cylinders, two steam and two air. 



130 



Air-Brake Catechism 



Q. Why is this pump named compound? 

A. Because in the steam end it uses the steam expansively 
in two cylinders, and in the air end it compounds the air 
in compression. 




Fig. 39. — 8^-Inch Cross-Compound Pump. 



Q. Is this type of pump more economical in the use of 
steam than the familiar types which have already been 
described? 

A. Yes, it is more economical in steam consumption, us- 



Cross-Compound Pump 131 

ing less than one-third the steam required by the 9^-inch 
Dump to compress the same quantity of air. 

Q. In general design and construction, how does it 
compare with the 9V2-iiich and 11-inch pumps? 

A. With the exception of the number of cylinders and 
he type of main slide valve^ it is of the same general plan. 

Q. Which are the steam cylinders and which are the 
bir? 

A. The t^vo upper C3dinders are the steam and the two 
ower the air^ this arrangement being the same as that of the 
Dther Westinghouse pumps. 

Q. What are the diameters of the respective cylinders? 

A. The smaller steam cylinder is 8^/2 inches^ the larger 
is 14% inches^ in diameter; the smaller air cylinder is 9 
nches^ and the larger 14% inches in diameter. 

Q. What names are used to distinguish these cylin- 
Kers? 

A. The smaller cylinders are called the high-pressure 
5team and the high-pressure air^ while the larger ones are 
ailed the low-pressure steam and the low-pressure air. 

Q. How are the high and the low-pressure cylinders 
arranged with respect to each other? 

A. The high-pressure steam cylinder is above the low- 
pressure air cylinder^ and the low-pressure steam is above 
;he high-pressure air cylinder. 

Q. What type of reversing-valve gear is employed in 
ihis pump? 

A. The same as in the 9i/2-inch and the 11-inch pumps. 

Q. Does it operate the same? 

A. Practically the same. 

Q. How are the pistons and the rods connected? 

A. The high-pressure steam and the low-pressure air pis- 



133 



Air-Brake Catechism 



€XHAU3T. -^ 






STEAM INLET. 




Fig. 40. — Diagram of Cross-Compound Pump. Up Stroke IIig] 

Pressure Side. 



Cross-Compound Pump 



133 



ST-tAM INLET. 




Fig. 41. — Diagram of Cross-Compound PuMr. Down Stroke, 

High-Pressure Side. 



134 Air-Beake Catechism 

tons are connected by one piston rod, and the low-press,ure 
steam and the high-pressure air pistons are connected by the 
other. 

Q. How many air valves has the pump, and what are 
they called? 

A. It has ten valves; there are four receiving, four inter- 
mediate, and two discharge valves. 

Q. How many air strainers has the pump? 

A. Two, one for the upper receiving valves and one for 
the lower. 

Q. In which air cylinder are the air-receiving valves 
located? 

A. In the low-pressure air cylinder. 

Q. Where are the intermediate air valves located? 

A. They are located between the low-pressure and the 
high-pressure air cylinder. 

Q. Where are the discharge valves located? 

A. They are located in the ends of the high-pressure air 
cylinder. 

Q. What is the difference between the main valve in 
the cross-compound and the ordinary D slide valve of the 
9V2-inch pump? 

A. The main valve in the cross-compound is made up of 
five pistons connected rigidly together; a large one on one 
end; a small one on the other; and three intermediate pis- 
tons all the same size. 

Q. What are Figs. 40 and 41, and what do they show? 

A. They are diagrammatic drawings of the cross-com- 
pound pump, and show the various ports and passages and 
the relative positions of the various parts on the up-stroke 
and the down-stroke of the pistons. 

Q. Explain the operation in the steam end on the up- 
stroke of the high-pressure steam piston. 



Cross-Compound Pump 135 

A. Eeferring to Fig. 40^ steam from the boiler enters the 
pump at the point marked '^steam inlet/' flows through pas- 
sage a to the top head and fills the main valve chamber be- 
tween the small and first intermediate pistons^ and also be- 
tween the third intermediate and large pistons. It also 
flows into the reversing valve chamber. The chamber D to 
the right of the large main-valve piston is connected to the 
exhaust through ports m and I. The small main valve piston 
is always connected to the exhaust through port c. The three 
intermediate pistons being equal in diameter are always bal- 
anced. The large and small pistons have steam pressure in- 
side and exhaust outside^ which results in forcing the main 
valve to the right to the position shown. This brings chamber 
h in register with port and passage g leading to the lower end 
of the high-pressure steam cylinders^ thus providing for the 
admission of live steam under the high-pressure steam pis- 
ton 7, starting it on its upward stroke. 

Q. Where does the steam go that was used in the high- 
pressure steam cylinder on the previous down stroke? 

A. Port c in the slide valve seat, w^hich leads into the up- 
per end of the high-pressure steam cylinder^ connects through 
chamber li with port d in its seat^ which leads into the upper 
end of the low-pressure cylinder^ thus the steam from above 
the high-pressure piston exhausts through port c, chamber h, 
and port d into the upper end of the low-pressure steam cyl- 
inder^ and drives the low-pressure piston on its down stroke. 

Q. How is the steam in the low-pressure cylinder below 
piston 8 released as the piston comes down? 

A. Port and passage / in the cylinder and top head is con- 
nected by chamber i with port e leading to the steam-exhaust 
pipe. 

Q. Does the low-pressure piston make its down stroke 
as the high-pressure piston makes its up stroke? 



136 Ajr-Brake Catechism 

A. Yes, and vice versa, as the low-pressure piston makes 
its up stroke tlie high-pressure piston makes its down stroke. 

Q. How is the stroke of the steam pistons reversed? 

A. When tlie Iiigh-pressure steam piston approaclies the 
upper end of its cylinder, the reversing plate 18 engages the 
shoulder on the reversing valve rod 21, forces this rod and 
the reversing valve 22, which is attached to it, upward to 
the position shown in Fig. 41. The reversing valve 22 in this 
position admits steam to chamber D outside the large piston 
through port n. This balances the large piston, and leaves 
the small piston alone unbalanced, having steam pressure on 
the right and exhaust on the left. This results in moving the 
main valve to the left as shown in Fig. 41. In the position 
shown, live steam enters the upper end of the high-pressure 
steam cylinder through chamber 1) and port c in its seat, thus 
causing the high-pressure steam piston to start on its down 
stroke. At the same time the high-pressure steam piston 
starts on its down stroke, the steam in the lower end of the 
high-pressure steam cylinder exhausts through port and pas- 
sage g in the slide-valve seat, chamber i, and port and passage 
/ leading to the lower end of the low-pressure steam cylinder 
and starts the low-pressure piston on its up stroke. The 
steam above piston 8 escapes to the atmosphere through port 
d, cavity li and port e. 

Q. Explain the operation in the air end. 

A. Commencing with the low-pressure air cylinder, it will 
be seen that as the low-pressure air piston is making its up 
stroke, it tends to form a vacuum behind it and the atmos- 
pheric pressure raises the lower air-inlet valves 38 and air 
flows into the cylinder past these valves, to fill the partial 
►vacuum formed by the moving air piston. The air contained 
in the cylinder above the piston is compressed, as the piston 
advances, and is forced past the intermediate air valves 39 into 
tlie upper end of the high-pressure air cylinder above the 



Cross-Compound Pump 137 

high-pressure piston 10. Upper air-inlet valves 37 are forced 
to their seat during the up stroke of the low-pressure piston, 
thus preventing the escape of any air back to the atmosphere. 
The air compressed by piston 9 on its up stroke is forced into 
the chamber above piston 10 and aids the steam acting down- 
ward on piston 8 to force pistons 8 and 10 downward. 

On the down stroke of the high-pressure air piston 10, the 
air under it which was previously forced into this cylinder, 
by the low-pressure air piston on its down stroke, is com- 
pressed to main reservoir pressure and forced out past the 
lower discharge valve 42 to the air-discharge pipe and the 
main reservoir. 

On the down stroke of the low-pressure and the up stroke 
of the high-pressure air pistons, the operations just explained 
are repeated, only the air is drawn in from the atmosphere 
past the upper discharge valves 37, and is discharged past 
lower intermediate valves 40 into the lower end of the high- 
pressure air cylinder, and is discharg'cd to the main reservoir 
past the upper discharge valve 41 into the air-discharge pipe 
and main reservoir. 

Q. What maximum pressure does the low-pressure air 
piston work against? 

A. About 40 pounds. 

Q. What maximum pressure does the high-pressure 
air piston work against? 

A. Main-reservoir pressure, whatever it may be. 

Q. How does the capacity of the cross-compound pump 
compare with that of the other air pumps? 

A. When working with 200 pounds steam pressure, against 
a main reservoir pressure of 130 pounds it has nearly three 
and one-third times the capacity of the 9V2-inch pump, two 
and one-quarter the capacity of the 11-incli pump, one and 



138 Air-Brake Catechism 

eight-tenths the capacity of the tandem compound pmnp/ 
and one and one-half tnnes the capacity of the New York 
No. 5 duplex pump. 

Q. Why is it that the air capacity of this pump is so 
much greater than that of any of the others? 

A. Making due allowance for its size^ its greater capacity 
and efficiency is due to its design which has cut down the 
clearance ratio to almost nothing, and because the air pistons 
have less difference of pressure on their two sides to work 
against, hence there is less packing-ring leakage encountered, 
and the pump runs cooler. 

Q. Is the low-pressure steam piston rod solid or hol- 
low? 

A. It is solid^ and this piston^ together with the high- 
pressure air piston^ is called a floating piston. 

Q. Why are they called floating pistons? 

A. They perform no part in reversing tlie pump. 

Q. About how many cycles per minute should the 
pump speed be? 

A. About 65^ and with 200 pounds of steam pressure it 
cannot be made to run any faster. 

Q. Then the pump cannot be raced? 

A. No^ not even against a comparatively low air pres- 
sure^ and it is practically impossible to create conditions which 
will result in any pounding. 

Q. With what steam pressures is this pump designed 
to operate? 

A. 160 pounds^ or more. 

Q. How should it be started, drained, and lubricated? 

A. The same general rules given for the other pumps 
apply in operating the compound. 



WESTIIs^GHOUSE PUMP GOVEENOES. 

The accompanying pump governor cut represents the old- 
style governor. 

Q. What does Fig. 42 illustrate? 

A. It shows a cross section of the old standard single pump 
governor, which has lately been superseded by the SF-4 du- 
plex type^ described on page 143. This single governor is. 
however^ still largely used. 

Q. Explain the duty of spring 41. 

A. The tension of the spring 41 is regulated by the cap 
nut 40 and holds down the diaphragm 42^ which in turn holds 
the small pin valve on its seat. 

The fitting 45 is connected to main-reservoir pressure. 
When the pressure entering at 45 and acting on the under 
side of the diaphragm 42 is greater than the tension of the 
spring 41^ the diaphragm is forced up^ thus lifting the pin 
valve^ from its seat. 

Q. What effect does unseating this pin valve have? 

A. It allows air pressure to reach the top of piston 28, 
(Fig. 42)^ forcing it down and closing valve 26. 
Q. What effect does closing valve 26 have? 

A. It almost shuts off the steam supply and slows down 
tlie pump^ so that it operates very slowdy. 

Q. Why does it not entirely stop the pump? 

A. A small port is drilled through valve 26 ^ which al- 
lows a small amount of steam to pass through to the pump, 
thus causing it to operate slowly^ thereby supplying the leak- 
age in the brake-pipe, and preventing the possibility of the 
pipes freezing in severe winter weather. 

Q. At the same time that air forces piston 28 down, 
where else does it go and with what effect? 



1^0 



Air-Beake Catechism 



^34->, 



TO BOILER 




TO MATfsf. RESERVOIR WtTJffJf^ 

CONNECTION 26 ON |l|(||||/ 

ENGINEE.R:,S BRAKE P 
VALVE 






TO PUMP 



Fig. 42. — Single Top Pump Governor. 



Pump Governors ^ 141 

A. It passes out of the small vent port, at which the 
arrow 37 points, to the atmosphere. 

Q. What is effected by any reduction of the main reser- 
voir pressure? 

A. An}^ reduction of main-reservoir pressure allows the 
spring 41 to force the pin valve to its seat, and what air still 
remains on top of piston 28 escapes through the vent port 37, 
and, with no pressure on top of piston 28, the spring 31 raises 
the piston 28 and valve 26, allowing full steam pressure from 
the boiler to reach the pump. 

Q. Of what use is the spring under the head of the 
pin valve? 

A. To hold the valve up when piston 43 is raised. Were 
it not for the spring, the pin valve would remain seated by 
gravity. 

Q. If any air should leak by piston 28, or any steam 
should leak by the stem of the valve 26 into the cavity 
under piston 28, how would it escape? 

A. There is an opening in the casing 32 connected to a 
drip pipe which leads to the atmosphere. 

Q. What effect would be noticed if this drip pipe be- 
came clogged with dirt or were frozen shut, when there 
was a leakage of steam up under the governor piston? 

A. Piston 28 could not be forced down, and the pump 
would not stop working until the main-reservoir pressure was 
about equal to boiler pressure. 

Q. What would be the effect fl the release port 37 
(Fig. 42) were closed by dirt? 

A. The pump would be very ^.low in starting to work 
after once stopping. 

Q. Why? 

A. Because^ when the pin valve closed, the cavity above 
piston 28 would be filled with main-reservoir pressure^ whicli 



142 Air-Brake Catechism 

» 

could escape only by leaking by the packing ring 29 and 
out to the atmosphere through the drip pipe. 

Q. What effect would dirt on the seat of the pin valve 
have? 

A. It would make a constant blow out of the vent port, 
and if air could leak in faster than it could get out of the 
vent port, the pump would either stop or work very slowly, 
even if the pump throttle were wide open. 

Q. Why would it work slowly? 

A. Because the pressure on piston 28 may force the valve 
26 partly shut and allow only a small amount of steam to 
reach the pump. If the leak were bad enough, the pump 
would be stopped entirely. 

Q. What effect would be noticed if the pin valve be- 
came gummed so that it would not seat centrally? 

A. Air would pass down on piston 28, and the ac- 
tion of the pump would be the same as just described, wdth 
dirt on the seat of this valve. 

Q. What would be the effect if the casing in which 
the governor piston works should become badly worn, 
and a worn ring 29 were replaced with a new one without 
truing the casing? 

A. When piston 28 was forced down a little farther than 
usual, it might stick, causing the pump to stop. A jar on 
the governor might start the pump. 

Q. Why was this type of governor superseded by the 
SF-4 type? 

A. So as to obtain the beneficial results of the duplex 
main-reservoir regulation in all equipments. This arrange- 
ment is described on page 174. 

Q. Is there any difference with these two governors in 
the principle of governing the pump? 

A. Iso; the only difference is that the pump can be 




MR 



MAIN RESERVOIR 
PRESSURE 



FEED- VALVE 
PRESSURE 



ATMOSPHERE 



LIVE STEAM 

FROM BOILER 

PRESSURE 



WASTE STEAM AT 

ATMOSPHERIC 

PRESSURE 



Fig. 48 ■■■— The SF-4 Pump Governor. The modified duplex pump- 
governor used in the No. 6 E T locomotive- brake equipment. 
MR— main-reservoir pipe, direct; ABV— pipe to automatic brake- 
valve; FVP— branch of feed valve pipe; B— steam pipe to 
boiler; P— connection with air pump; W— waste-pipe comiection. 



Copyright, 1909, by The Norman W. Heuley Publishing Co. 



Pump Governors 143 

iitomatically governed at two different pressures, depending 
►n the position of the brake-valve handle. 

The Present Standard (SF-4) Pump Governor. 

Q. What is represented in Fig. 43? 

A. The new duplex pump governor^ used with all present 
tandard locomotive brake equipments. 
Q. Of what does the duplex governor consist? 

A. Of two pressure heads which operate in conjunction 
\'ith one steam portion of the governor. The former type 
)f duplex governor was made by unscrewing the entire pres- 

ure head from the cylinder cap 27^ Fig. 42^ and replacing it 
^vith a "^^siamese fitting/^ No. 14^ Fig. 43, which was arranged 

or two pressure heads^ both just alike^ and placed side by 
dde. 

Q. In what respect does this SF-4 type of duplex gov- 
nnor differ from the former standard? 

A. One of the pressure heads has two air connections and 
m excess-pressure regulating spring; in operation this head 
lutomatically maintains the excess-pressure for which it is 
idjusted^ regardless of what the brake-pipe pressure may be. 

Q. At what point is the additional air connection 
made? 

A. To the side of the upper portion above the diaphragm 

128. 

Q. What pressure is always in the upper part of the 
excess-pressure head? 

A. Brake-pipe pressure. 

Q. What pressure is in chamber d under diaphragm 
28? 

A. When the handle of the automatic brake valve is in 



144 Air-Brake Catechism 

release or running positions, main-reservoir pressure is in this 
chamber. 

Q. When the brake-valve handle is not in running or 
release positions, what happens? 

A. The excess-pressure head is cut out of operation, the 
pump then being under the control of the other pressure head. 

Q. What is the other pressure head called? 

A. The '^'^maximum-pressure^^ head. 
Q. What pressure is in chamber a under diaphragm 
20, and when? 

A. Main-reservoir pressure, at all times. 

Q. When the brake-valve handle is in release or run- 
ning positions, and main-reservoir pressure is under both 
diaphragms, why does not the maximum-pressure head 
stop the pump? 

A. Because the regulation of spring 19 is for a higher 
pressure than is obtained in chamber d. This is fully ex- 
plained under Duplex Main-Eeservoir Regulation on page 
174. 

Q. Aside from the excess-pressure head and its air 
connection, is the SF-4 pump governor the same in con- 
struction, design and operation as the older standard du- 
plex pump governor? 

A. Yes, just the same. 

Q. Should care be exercised to keep all air connections 
tight and all ports in and around the governor open? 

A. In order to get satisfactory results all the pipe con- 
nections should be maintained perfectly tight and free from 
leakage, and all the vent ports should be kept open. 

Q. If any of the pipe connections should leak, what 
would be the result? 

A. A waste of air, tlie amount depending on the size of 
the leaks. 



Pump GovER^^ORS 145 

Q. How is the SF-4 pump governor adjusted to main- 
tain the proper excess pressure? 

A. By removing the cap nut on the excess-pressure top, 
and screwing down on the regulating screw 26 to increase 
excess-pressure; and by screwing up on this screw to reduce 
it. 






CHAPTEE V 

MAIN RESERVOIR 

Q. Where does the air go when it leaves the pump? 

A. To the main reservoir. 

Q. Where does main reservoir pressure begin and 
where end? 

A. It begins where the air leaves the pump and ends at 
the engineer's valve. 

Q. What is the object of the main reservoir? 

A. Its object is to act as a storehouse in which to keep 
a reserve pressure to put into the brake-pipe to release brakes 
and recharge auxiliaries. It also acts to collect most of the 
dirt, oil, and moisture that leaves the pump, and condenses 
as the air cools. 

Q. How much main reservoir pressure is usually car- 
ried? 

A. Usually ninety pounds, although more is used in moun- 
tainous country, when using the High-Speed Brake, the 
High-Pressure Control, or the Duplex Method of Main Ees- 
ervoir Eegulation. ^ 

Q. What size main reservoir is considered proper? 

A. One whose capacity is not less than 50,000 cubic 
inches for freight, and 40,030 or more for passenger engine, 
according to the kind of service in wliich the engine is placed. 
Best results are obtained in freight service by using a main- 
reservoir capacity of 70,000 cubic inches, where the trains | 
are of considerable length. 



Mai^ Reservoir 147 

Q. How large should any main reservoir be? 

A. In releasing brakes in any service the main reservoir 
must be large enough so that^ when the brakes are applied and 
we wish to release them^ the main reservoir pressure will 
equalize with that in the brake-pipe^ when connected with 
it^ at a sufficiently high pressure to insure the prompt and 
certain release of the brakes. 

Q. Why is a larger main reservoir necessary in freight 
than in passenger service? 

A. Because there are a greater number of auxiliary res- 
ervoirs to charge in freight service and a longer brake-pipe 
to supply. 

Q. When is a large main reservoir with full pressure 
most essential? 

A. After an emergency application, and especially after 
a break in two. 

Q. What results are likely to follow the use of small 
main reservoirs on engines pulling long trains? 

A. The pump is likely to heat^ brakes are likely to sticky 
we will have a hard handling rotary, and the recharge is ac- 
complished more slowly. 

Q. Why is a pump more likely to heat with a small 
main reservoir? 

A. Because the smaller the main reservoir, the higher the 
pressure has to be carried, and the higher the jiressure the 
more is heat generated in compressing the air; therefore the 
pump is more likely to heat and burn out the packing. 

A second reason is that with a small reservoir, when re- 
leasing brakes, the pump must operate faster to charge the 
auxiliary-reservoirs before the speed of the train increases too 
much. The pump working very fast does not have time to 
take in a full cylinder of air each stroke ; it then makes more 



148 Air-Brake Catechism 

strokes to compress the same amount of air^ "than it wonlcl 
were it working more slowly. 

Q. State the gains made by using a large main reser- 
voir? 

A. Pressure in the main reservoir and brake-pipe will 
equalize higher when releasing, auxiliary-reservoirs will be 
charged more quickly, the pump is not so likely to heat, and, 
not working so rapidly or against so high a pressure, will not 
wear out so fast, and the brakes are not so likely to stick. 

Q. What should be the location of a main reservoir? 

A. If possible, at the lowest j^oint in the air-brake system. 

Q. Why? 

A. To have all the dirt, oil, and moisture possible drained 
into it and drawn off through the drain cock. 

Q. Where is the main reservoir usually located? 

A. On each side under the running board. 

Q. Should it be located there? 

A. Yes, when it is possible to place there a main reser- 
voir of the regulation size ; but the size must not be sacrificed 
for the position. 

Q. Is it right to locate it on the tank? 

A. Yes, if the requisite volume can be obtained in no 
other way; otherwise no. 

Q. Why is it not a desirable position? 

A. Oil and dirt will not drain into it as they should and 
when it is so located two extra lines of hose must run be- 
tween the tank and engine, one to carry the air from the 
pump to the main reservoir, and the other to bring the pres- 
sure from the reservoir to the engineer's valve. These hose 
get full of oil and dirt, decay, burst, and in the end prove 
very expensive. 

Q. How often should the main reservoir be drained? 

A. At the end of each trip. 



Main Eeservoir 



149 



Q. Where does the water found in the main reservoir 
come from? 

A. It is drawn from the atmosphere^ and deposited as 
the air cools. 

Q. Does any of the condensed steam from the steam 



" ^^Pipe Thread 




Fig. 44. — Main Reservoir Drain Cock. 



end of the pump leak by the piston rod and then pass into 
the main reservoir with the compressed air? 

A. A trifle; but this is an inappreciable amount com- 
pared with what comes from the atmosphere^ especially on 
rainy days. 

Q. What is generally conceded to be the best prac- 
tice concerning main reservoirs? 



150 Air-Brake Catechism 

A. To use two main-reservoirs^ preferably- long and of 
small diameter^ and a cooling pipe of approximately 25 feet 
between the pmnp and first reservoir, and 25 feet between 
the first and second reservoirs. 

Q. Why is this done? 

A. Tests have shown that^ with these conditions existing^ 
air cools j)roperly before passing the brake valve and no water 
is found in the brake-pipe^ thus doing away with the chance 
of frozen brake-pipes. 

The accompanying cut represents the drain cock for the 
main reservoir. This valve is screwed into the main reser- 
voir^ and its operation is so simple that an explanation will 
be unnecessary. 

WESTIXGHOUSE (G-6) EXGIXEER'S BEAKE VALVE 

Q. What was the first form of valve used? 

A. That which was known as the old three-Avay cock. 

Q. With what equipment was this used? 

A. With the straight air. with the plain automatic^ and 
for a time^ by a good many roads^ with the quick-action 
brake. 

Q. What objection was there to it? 

A. It was not sufficiently sensitive^ and there was great 
danger of throwing the brakes into emergency. 

Q. Why? 

A. Because reductions of brake-pipe pressure were made 
by instinct or sense of sound. An engineer having a short 
train to-day and a long one to-morrow could scarcely avoid 
doing poor braking, as his valve was nothing much more than 
a plug valve. A reduction that was a trifle too heavy would 



G-6 Engineer's Brake Valve 



151 



throw the triples into quick action^ and on a long train the 
reduction could not be made too slow^ or the air would blow 
through the leakage grooves in the brake cylinders. If the 
escape of air from the brake-pipe were suddenly checked^ the 
air from the rear rushing ahead has a tendency to kick off 
some of the head brakes. 

Q. In changing the valve what was the object? 

A. To obtain a valve that would mechanically and grad- 




Fig. 45. — Showing Flow of Air through Brake Valve when in 

Full Release Position. 



ually make the desired reduction of brake-pipe pressure^ re- 
gardless of the length of the train. 

Q. Explain the different parts of the engineer's brake 
valve. 



152 



Air-Brake Catechism 



A. Y, 1\ W, and R are explained by referring to Figs. 46, 
47, and 48 ; X connects with the main-reservoir. 

31 and 32 are known respectively as upper and lower body 
gasket. 

14 is the rotary valve. 



TO GAUGE 
BLACK HAND 
tfiAiN PIPE PRESSURE 



TO EOUALIZiNO 
RESERVOIR 




Fig. 46. — G 6 Engineer's Brake Valve, Release Position. 



13 a gasket to keep main-reservoir pressure from leaking 
to the atmosphere. 

The space above piston 18 is known as cavity D; tliis 
cavity is connected with the little drum, or equalizing re- 
servoir, by the pipe 21. 



G-6 Engineer's Brake Valve 



153 



18 is the equalizing piston, 22 the brake-pipe exhaust. 

3 is the rotary value seat, and 1 is the valve body. 

There is a tee in pipe 26 just after it leaves the valve, one 
branch of which goes to the red hand on the gauge and the 
other to the pump governor. 

The other parts need no naming. 




Fig. 47. — G 6 Engineer's Brake Valve, Running Position. 



Q. Of what use is the engineer's valve? 

A. To give the engineer complete control of the flow 
of air. 



154 



Air-Brake Catechism 



Q. How many positions are there for the engineer's 
valve? 
A. Five. 

Q. Name them. 

A. Eelease, running, lap, service, and emergency posi- 
tions. 



TO Pl/MP GOVERNOR & GAUGE S So 

RED HAND ' ^ - "• 



TO EQUALrrrNG 

RESERVOIR 




,Ve PIPE Tf\& 



Fig. 48. — G 6 Engineer's Brake Valve, Plan View. 



Q. Describe the use of the different positions. 

A. Kelease is that used for releasing brakes. 

Eunning position is the one used when running on the 
road and when the brakes are inoperative. 

Lap position is that which blanks all ports in the valve. 

Service is the position used when the brakes are to be 
applied gradually. 



G-6 Engineer's Brake Valve 155 

Emergency is the position used when the brakes are to 
be applied suddenly and with maximum power. 

Q. What connections do we have with the valve in 
release? 

A. A direct connection between the main reservoir and 
brake-pipe through a large port^ and between the main res- 
ervoir and cavity D, or the little drum^ through two small 
ports. 

Q. Explain the flow of air from the main reservoir 
through the engineer's valve in this position. 

A. In this position the main-reservoir pressure enters 
the valve at X, passes through port A, port a of the ro- 
tary 14^ port & of the rotary seat 3 (Figs. 45^ 46 and 48)^ 
up into cavity c of the rotary and through port I into the 
brake-pipe at Y. As the air passes through cavity c of the 
rotary on its way to the brake-pipe^ it is free to pass through 
port g (Fig. 46) into cavity D. In this position^ port j 
of the rotary (Fig. 51) is over port e in the rotary seat (Fig. 
46) also leading to the little drum^ or cavity D. 

Q. Can main reservoir pressure reach the top of the 
rotary 14 at all times? 

A. Yes. 

Q. What is the valve shown in Fig. 45? 

A. It is the top portion of the old D 8 Brake Valve^ 
a cut of which is inserted to convey a better idea of the 
flow of air through the brake valve in release position. 

Q. Does the passage of air through D 8 correspond to 
that of the G 6 Brake Valve in release position? 

A. Although the valves are somewhat different in con- 
struction, the flow of air in release position is practically the 
same in both brake valves. 

Q. How much main reservoir pressure is usually car- 
ried except in very mountainous country? 



156 



Air-Beake Catechism 



about as large 



A. Mnety to one hundred pounds; in the description of 
the valve it will be considered that 90 pounds is used. 

Q. How much pressure would we get in the main reser-l 
voir, the brake-pipe and the little drum, were the handle 
of the engineer's valve to be left in full release position] 
until the pump stopped? 

A. Xinety pounds in each, as there is a direct con-i 
nection between the three. 

Q. What is the small blow we hear if the engineer') 
valve is allowed to remain in full release? 

A. It is the escape of main-reservoir pressure through 
the warning port of the rotary into the emergency exhaust 
(Fig. 48) and out to the atmosphere. 

Q. What is this port and its purpose? 

A, It is a port, one end of which is aoout as large as 
a pin. WTien the engineer hears this blow it means to liinj 
that he must be careful or he will get ninety pounds presj 
sure in the brake-pipe if he leaves the handle of his valv 
in full release position too long. 

Q. How much pressure is usually carried in the brak( 
pipe and little drum in country not mountainous? 

A. Seventy pounds. 

Q. How does the engineer prevent a ninety-poum 
pressure accumulating in the brake-pipe and little druml 

A. By moving the valve to the second^ or running posi| 
tion. 

Q. Why do we get only seventy pounds pressure i 
the brake-pipe with the valve in running position? 

A. Because in this position all air passing into the bral 
pipe from the main reservoir has to pass through the fee 
valve (Fig. 4:7), and this is adjusted to close as soon as tliei 
is a seventy-pound pressure in the brakc-i^ipe 



\ii 



G-C) Engineer's Brake Yalve 157 

Q. In running position we have the position of the 
rotary as shown in Fig. 47. Explain the passage of air 
in this position. 

A, The main-reservoir pressure passes through the ports 
j, f and f (Fig. 47 and 51) into the feed valve^ or brake- 
pipe governor as it is more commonly called; thence through 
port i (Fig. 48) into port I (Figs. 46 and 48) and out into 
the brake-pipe at Y, As the pressure passes through port I 
into the brake-pipe it is also free to pass up into cavity c 
of the rotary^ which is still over port I, as seen in Fig. 47. 
Port g is still exposed under cavity c, and at the same time 
the air passes through the brake-pipe governor into the brake- 
pipe^ it also passes info cavity c of the rotary, port g of the 
" rotary seat (Fig. 47) and into cavity D, or the little drum. 

Q. The brake-pipe governor closes when there is sev- 
enty pounds in the brake-pipe with the valve in running 
position. How much pressure do we get in the main reser- 
voir with the valve in this position? 

A. Xinety pounds. 

Q. What stops the pump when there is ninety pounds 
in the main reservoir? 

A. The pump governor, which is connected with main- 
reservoir pressure at 26 (Fig. 46). 

Q. Is the pump governor always set at ninety pounds? 

A. ^0 ; only in level and hilly country. In mountainous 
country, it is set much higher, also in level country where 
exceptionally long trains are handled. 

Q. The red hand on the gage represents main reser- 
voir pressure, and the black hand is said to represent 
that on the brake-pipe. Is the pipe leading to the black 
hand connected directly to the brake-pipe? 

A. No; it is connected to the little drum pressure. (See 21, 
Fig. 46.) 



158 Air-Brake Catechism 

Q. Why is it called brake-pipe pressure if not connect- 
ed to it? . 

A. Because in full release or running position port g 
furnishes a direct connection between the little drum and 
brake-pipe^, and the pressures must be equal. 

Q. What is the next position to the right of running 
position? 

A. Lap position. 

Q. How does the air flow with the valve in this posi- 
tion? 

A. There is no passage of the air as all ports are blanked. 
The rotary is moved around sufficiently to shut off port / 
in the rotary from port / in the rotary seat, and a small lug 
on the inside rim of the rotary also covers port g, thus separa- 
ting the brake-pipe from the little drum. In this position 
the main reservoir^ brake-pipe and little drum pressures are 
each by themselves. 

Q. What is the dividing line between the brake-pipe 
and little drum pressures in this position? 

A. The equalizing piston 18 (Fig. 4G). 

Q. Do we still refer to the black hand as representing 
brake-pipe pressure on lap, knowing the ports are closed 
between the little drum and brake-pipe? 

A. Yes. 

Q. If there were a leak from the brake-pipe, would the 
black hand fall back if the valve is on lap? 

A. Yes. but slowly. 

Q. Why? 

A. Because to have piston 18 work smoothly the packing 
ring 19 (Fig. 4G) must not be absolutely tight. If the 
brake-pipe leaks^ the little drum pressure will gradually leak 
by the packing ring into the brake-pipe and equalize with 
it. 



G-6 Engin^eer's Brake AT'alve 159 

Q. What would happen if this packing ring were 

tight? 

A. With the valve on lap all brake-pipe pressure could 
leak away and the black hand on the gauge would not show 
it. 

Q. What is the next position to the right of lap? 

A. Service ]30sition. 

Q. What is this position used for? 

A. To make a gradual application of the brakes. 

Q. Explain this position. 

A. In this position^ a groove p (Fig. '52) of the rotary 
connects port e (Fig. i8) leading to the little drum through 
rotary seat with a groove li (Fig. 48) also in the rotary seat 
li leads into the emergency exhaust h (Fig. 48)^ which is di- 
rectly connected with the atmosphere as shown by the dot- 
ted lines. We then have a direct connection from the lit- 
tle drum to the atmosphere through small ports. 

Q. What is port e called? 

A. The preliminary exhaust port. This hole is bushed, 
and the bushing has a small taper hole through it. 

Q. In what two positions is it that the preliminary 
exhaust port e is used? 

A. In the release position and also in the service po- 
sition. 

Q. What is its use in the release position of the brake 
valve? 

A. To permit main reservoir pressure to feed down into 
chamber D above the equalizing piston 18, as shown in 
Fig. 46. 

Q. What is this port used for in the service position 
of the brake valve? 

A. It is used to permit the pressure above the equalizing 



160 Air-Brake Catechism 

piston, connected with the equalizing reservoir through port s 
to escape to the atmosphere. 

Q. What effect does taking air from the little drum 
have? 

A. It reduces the pressure on top of piston 18. The 
pressures were the same on both sides of it, but when the re- 
duction is made from the little drum in service position, 
it leaves piston 18 with the greater pressure underneath on 
the brake-pipe side of the piston. 

Q. What effect has this? 

A. The brake-pipe pressure being greater forces piston 
18 from its seat and allows brake-pipe pressure to escape 
to the atmosi^here through the brake-pipe exhaust 22 (Fig. 
4G). 

Q. How long does piston 18 remain off its seat? 

A. Just as long as the brake-pipe pressure is greater than 
that in the little drum. When the little drum pressure is a 
trifle greater than that in the brake-pipe, piston 18 is forced 
to its seat. 

Q. Do we still speak of the black hand as representing 
brake-pipe pressure? 
A. Yes. 

Q. How do we know it is the same as that in the little 
drum to'which the gage pipe leading to the black hand is 
connected? 

A. Because the equalizing piston will take the same 
amount of pressure from the brake-pipe before it closes that 
the engineer took from the little drum. 

Q. If the engineer wishes to apply brakes gradually, 
does he take air from the brake-pipe? 

A. No; he takes it from the little drum, and piston 18 
takes care of the brake-pipe. 



G-6 Engineer's Brake Valve 161 

Q. To what else in the brake system is the piston 18 
similar in its work? 

A. The triple-valve piston. 

Q. What is the next position to the right of service? 

A. Emergency position. 

Q. Explain this position. 

A. The rotary is moved around so that the large cavity 
c (Fig. 52) is directly over the large ports I and h of the 
rotary seat (Fig. 48). Air passes from the brake-pipe at I 
into cavity c and out to the atmosphere through port k. 

Q. What is the object of using the large ports? 

A. To get a very sudden reduction in the brake-pipe to 
cause the triple valves to go into quick action. 

Q. Is the reduction necessarily heavy to obtain quick- 
action. 

A. No; it is quick. 

Q. Does the little drum pressure or the equalizing pis- 
ton play any part in the emergency application? 

A. i^one whatever. 

Q. In running position when the pump stops we have 
ninety pounds in the main reservoir and seventy on the 
brake-pipe. What is the difference between the pressure 
in the main reservoir and the brake-pipe called? 

A. Excess pressure. 

Q. What is the .use of excess pressure? 

A. It is a reserve pressure to throw into the brake-pipe^ 
when the valve is placed in release position, to force the triple 
pistons to release position and help recharge the auxiliary 
reservoirs. 

Q. If the pump were started with the handle of the 
valve on lap, how much pressure would we get in the main 
reservoir and how much in the brake-pipe? 



163 



Air-Brake Catechism 



A. Xinety pounds in the main reservoir and nothing in 
the brake-pipe. 

Westinghouse Slide- Valve Feed A^ilve. 

Q. What is the object of the Slide- Valve Feed Valve 
illustrated in Figs. 49 and 50? 



ee 65 64 




Fig. 49. — Slide-Valve Feed Yalve. 

A. To maintain a constant pressure in the brake-pipe^ 
when the brake valve is in running position. It contains great- 
er refinement of, and a more positive action than, the older 
form of feed valve, or train-line governor, as it is often des- 
ignated. It fastens to the same studs as the old valve and 
is interchangeable. Fig. 49 shows a central section through 
the supply valve case. Fig. 50 is a central section through 



Slide-Valye Feed Valve 



163 



the regulating valve and spring box and a transverse section 
through the supply valve case. 
Q. Explain the operation of this valve. 

A. Ports /' and i (Fig. 50) register with the correspond- 
ing ports in the brake valve body (Fig. 48) ; main-reservoir 
pressure can reach the feed valve through port / only when 




Fig. 50. — Slide- Valve Feed Valve. 



the brake valve is in running position. In this position it 
has free access through /' and / with chamber F, Chamber E, 
which is separated from chamber F by the supply valve pis- 
ton 54^ is connected with passage i and thus with the brake- 
pipe through passage, c, c, port a (controlled by regulating 
valve 59)^ and chamber G over diaphragm 57. Eegulating 
valve 59 is normally held open by diaphragm 57 and regula- 
ting spring 67, the tension of which is adjusted by regu- 



164 



Air-Brake Catechism 



lating nut 65. When this valve is unseated chamber E is in 
communication with the brake-pipe, and is subject to it's pres- 

sure. 

When the handle of the brake valve is placed in running 
position, air pressure from the main reservoir enters chamber 
F and forces supply-valve piston 54 forward, compressing 
spring 58, drawing supply valve 55 with it, thus uncovering 
port b. It thereby gains entrance directly into the brake^ 
pipe through ports i i. The resulting increase of pressure in 
the brake-pipe (and in chamber G over diaphragm 57) con 
tinues until it becomes sufficient to overcome the tension by 





Fig. 51. — Tor View of 
Rotary Valve. 



Fig. 52. — Bottom View o] 
Rotary Valve. 



regulating spring 67, previously adjusted at 70 pounds. Dia> 
phragm 57 then yields and permits the regulating valve 59 tc 
be seated by spring 60, closing port a and cutting ofE com- 
munication between chamber E and the brake-pipe. Th- 
pressures in chambers E and F now equalize quickly througl 
leakage past supply-valve piston 54, and the supply-valv 
piston spring 58, previously compressed when the supply 
valve was forced to the right, now reacts and forces supply 
valve piston 54 and supply-valve 55 to their normal posi 
tions, closing port h and cutting off communication betwee: 
the main reservoir and brake-pipe. 



Slide- Valve Feed Valve 165 

Q. What causes the feed valve to again permit main 
reservoir pressure to reach the brake-pipe? 

A. A subsequent reduction of brake-pipe pressure^ either 
by leakage or otherwise, reduces the pressure in chamber G 
and permits regulating spring 67 to force diaphragm 57 up, 
thus unseating regulating valve 59, thereby j)ermitting the 
pressure accumulated in chamber E to discharge into the 
brake-pipe through ports c, c and a, chamber G and port i. The 
equilibrium of pressures upon the opposite faces of supply- 
valve piston 54, being thus destroyed, the higher main-reser- 
voir pressure in chamber F again forces supply- valve piston 
5dt, and it in turix draws the supply- valve 55 over 
so as to expose port h, which again permits the brake-pipe 
pressure to be restored to a pressure of 70 pounds, or other 
predetermined amount. 

Q. How can the brake-pipe pressure be changed when 
using this feed valve? 

A. Eemove the cap 66^ turn the adjusting nut 65 in, to 
increase brake-pipe pressure, and out to reduce it. 

Q. What could be wrong if the brake-pipe pressure 
equalized with that in the main reservoir and this could 
not be changed by readjusting the tension of the regulat- 
ing spring 67? 

A. Aside from the causes already explained in connec- 
tion with the brake valve proper, there might be a leak be- 
tween ports /' and i in the gasket, between the feed valve 
and brake valve proper; dirt on the seat of the supply valve 
55, or the regulating valve 59, or a poor seat on either; or 
the part of the regulating valve stem that rests upon dia- 
phragm 57 being too long. Dirt on diaphragm 57, which 
would liold regulating valve 59 unseated, would produce 
the same result. 



166 Air-Beake Catechism 

Q. What could make the regulating valve stem too 
long? 

A. By grinding the valve in. After this is done it shoulc 
be noted that the end of the stem is flush with the projec- 
tion of the casting upon which diaphragm 57 rests. 

Q. Why would dirt on the seat of the regulating valve 
59 cause brake-pipe pressure to become too high? 

A. Witli dirt on the seat of the regulating valve 59 air 
from chamber E, at the right of piston 5^, could escape to the 
brake-pipe. If it escaped faster than main-reservoir pressure 
could leak by the piston 54, the pressure in chamber E woulc 
be less than that in chamber F, and the supply valve 55 and 
piston 54 would be moved to the right, exposing port &, which 
connects main-reservoir and brake-pipe pressures^ and the 
brake-pipe would be overcharged. 

Q. What is the object of the brass button at the end 
of the supply- valve piston spring 58? 

A. As a spring is compressed there is a winding action 
set up^ and a tendency for the spring to turn the piston, and 
the piston in turn to twist the supply valve from its seat. 
By the use of the button there is no chance for this action 
as a very slight bearing is in contact between the button and 
piston. The effect of the winding action of the spring on the 
piston is thus destroyed. 

Q. Name the different parts of the slide-valve feed 
valve. 

A. 51, the body; 52, the flush nut; 53, cap nut; 51, sup- 
ply-valve piston; 55^ supply valve; 56, supplj^-valve spring; 
57, diaphragm; 58, supply- valve piston spring; 59, regula- 
ting valve; 60, regulating- valve spring; 61, regulating-valve 
cap nut; 62, spring box; 63, diaphragm ring; 6-1. diaphragm 
spindle; 65, adjusting nut; QQ>^ check nut, and 67, the ad- 
justing spring. 



The Equalizing Eeservoir 167 

The Equalizing Eeselvoir, 
OR Little Drum, or Cavity D. 

Q. How is the little drum, or cavity D, usually spoker 
of? 

A. As the equalizing auxiliary. 

Q. Where is the little drum usually located? 

A. Under the foot-boards of the cab, on either the fire- 
man's or engineer's side, according to which has the most free 
sj)ace. 




Fig. 53.— The Little Drum, or Cavity D. 



Q. What is the object of the little drum? 

A. To furnish a volume of air on top of the equalizing 
piston in the engineer's valve. 

Q. Would not the air in the small cavity over the 
equalizing piston hold air enough to keep the piston on 
its seat? 

A. Yes ; but there is not a sufficient volume there to draw 
from in making service reductions to make them sufficiently 
gradual. 



168 Air-Brake Catechism 

Q. What would happen when the engineer put tke 
handle of the engineer's valve in service position, if there 
were no little drum to furnish a volume of air on top of 
the equalizing piston? 

A. The air would leave the top of tlie piston in a flash 
on account of the small volume^ the black hand on the gauge 
would fall to the pin, the equalizing piston rise full stroke, 
all brake-pipe pressure would rush to the atmosphere through 
the brake-j^ipe exhaust^ and the engineer would have lost con- 
trol of the brakes. 

Q. How would the brakes on the train act? 

A. If a long train were coupled to the engine^ the brakes 
would set with a full service application ; but if a train of less 
than about six or seven cars^ the brakes might go into quick- 
action. 

Q. Why full service on a long train and quick-action 
on a short one? 

A. On a short train^ when the equalizing piston flew up, 
air from the brake-pipe would go to the atmosphere through 
the brake-pipe exhaust faster than the auxiliary-reservoir 
pressure could get from the auxiliary to the brake cylinder 
through the service port of the triple slide valve. When the 
auxiliary pressures were enough stronger than that on tlie 
brake-pipe, they would force out the triple pistons and com- 
press the graduating springs, causing the triples to go into 
quick-action. 

On a train of considerable length the brake-pipe pressure, 
due to the greater volume on the brake-pipe, could not get 
out of the brake-pipe exhaust any faster than the auxiliary- 
reservoir pressure could feed through the slide valves to the 
brake cylinders, and the auxiliary-reservoir pressures would 
not be strong enough to compress the graduating springs, 
but, losing all brake-pipe pressure, would apply the brakes 
in full-service application. 



The Equalizing Eeservoir 169 

Q. The three-way cock was done away with to get a 
valve that would mechanically make a gradual brake- 
pipe reduction regardless of the length of the train. What 
is it about the valve now used that allows this to be done? 

A. The little drum in conjunction with the equalizing 
piston. 

Q. Does an engineer have to leave the handle of the 
engineer's valve in service position any longer to make a 
reduction of five pounds on a long train than en a short 
one? 

A. No; all little drums are of the same size. If a five- 
pound brake-pipe reduction is desired^ the engineer releases 
five pounds from the little drum to the atmosphere, and 
the equalizing piston takes care of tlie brake-pipe pressure 
regardless of the length of the train. 

Q. If by any chance the pipe leading to the little drum 
were broken off, could we still handle the brakes? 

A. Yes. 

Q. How? 

A. Plug the broken pipe and also the brake-pipe ex- 
haust. When wishing to apply the brakes in service, our 
service position would be of no use as the brake-pipe ex- 
haust is plugged; so move the valve part way into emergency 
position, being careful not to get it too far so as to make 
too sudden a reduction, and when putting the valve back 
on lap do not stop the brake-pipe reduction too quickly or 
the surge of air forward may release some of the head brakes. 

Q. In such a case, into what have we transformed our 
efficient valve? 

A. Practically into an old three-way cock. 

Q. How do we tell if the preliminary exhaust port e 
is free from gum and corrosion? 

A, Place the engineer's valve in service position and 



170 Air-Brake Catechism 

watch the black hand on the gauge. It should take about 
seven seconds to reduce the pressure in the standard little 
drum (10" x I-II/2":, about 770 cubic inches), from seventy 
to fifty pounds through the preliminary exhaust port. 

Q. What, besides the fact that the preliminary exhaust 
port is partially closed, would cause it to take longer than 
seven seconds to make this reduction? 

A. See the engineer's valve (Fig. -16). If the gasket 32 
leaked between the main reservoir and little drum, or between 
the brake-pipe and little drum, or if the packing ring 19 were 
sufficiently loose to allow brake-pipe pressure to feed by too 
quickly. 

Q. If it takes less than seven seconds to make this 
reduction, what is probably the matter? 

A. There is a leak somewhere in the connection to the 
little drum, which helps make the reduction. 

Peculiarities xVxd Troubles of the G-G Brake Valve. 

Q. What two troubles in the engineer's valve aside 
from those in the brake-pipe feed valve would not permit 
any excess pressure with the handle of the engineer's 
valve in running position? 

A. A leak in the lower gasket 32 (Fig. 4G) between 
the main reservoir and the little drum and a leaky rotary. 

Q. Why does air leaking from the main reservoir to 
the little drum in running position not permut any excess 
pressure? 

A. Because in this position the little drum and brake- 
pipe are directly connected. 

Q. Does gasket 32 leak very often? 

A. No; this is a trouble seldom encountered. 



G-6 Bkake Valve, Peculiarities and Troubles 171 

Q. What indications are given by such a leak? 

A. In service position it would take longer to make a 
given reduction on the little drum, as air is feeding in slow- 
ly at the same time it is being taken out through the prelim- 
inary exhaust. As soon as the valve was placed on lap the 
black hand would cjuickly feed up to main-reservoir pressure. 

Q. If the air were leaking into the little drum by gas- 
ket 32 as fast as it was being removed through the prelim- 
inary exhaust port, what would happen? 

A. The equalizing piston could not be raised and the 
only way the brakes could be applied would be by using the 
emergency position. 

Q. How does the leaking of the rotary do away with 
excess? 

A. The air from the main reservoir leaks under the ro- 
tary seat directly into the brake-pipe. 

Q. What harm besides that of destroying excess will 
result from a leaky rotary? 

A. We get main-reservoir pressure in the brake-pipe and 
consequently in the auxiliary-reservoirs, and the use of ninety 
instead of seventy pounds for braking purposes would slide 
tlie wheels. After the brakes were applied and the valve 
was on lap^ air leaking into the brake-pipe from tlie main 
reservoir would gradually increase brake-pipe pressure and 
force triples to release position. Without the proper excess 
it would also be hard to release brakes. 

Q. How would you test for a leaky rotary? 

A. Start the pump with the valve handle on lap. If the 
black hand starts, the rotary leaks. Gasket 2 leaking would 
also cause this, but this leak so seldom happens, it may be 
disregarded in practice. 

Q. Give another way of testing for a leaky rotary. 

A. Put the valve on lap and drain everything but the 



172 Air-Brake Catechism 

main reservoir ; open the angle cock at tlie rear of the tender 
and put the hose in a pail of water. If bubbles rise to the 
surface the rotary is leaking. 

Q. Which is the better test? 

A. The second is the more delicate test^ but the first 
is sufficiently practical and is easier. 

Q. Why should everything be drained in making the 
water test? 

A. Because with all air taken from the brake-pipe by 
opening the angle cock at the rear of the tender^ air leaking 
by the packing ring 19 in the piston 18 into the brake-pipe 
would cause bubbles to rise to the surface of the water. 
The same thing would result if air from the tender and driver 
brake auxiliary-reservoirs leaked by the triple-piston packing 
rings. The bubbles w^ould seem to indicate a leaky rotary, 
while it was merely an improperly conducted test. 

Q. Why can we sometimes get no excess with the valve 
in running position when the engine is alone, although the 
hands will stand properly at ninety and seventy when 
the engine is coupled to a train? 

A. It simply means that when coupled to a train the 
leaks on the train compensate for the leak through the en- 
gineer's valve. 

Q. What will cause a constant leak out of the brake- 
pipe exhaust 22 (Fig. 46), whether the valve is on full re- 
lease, running, or lap position? 

A;. Dirt on the scat of the valve at the end of the stem 
of piston 18. 

Q. What is the trouble if this leak does not exist in 
f iflll release or running position, but begins as soon as the 
valve is placed on lap? 

A. A leakage of little-drum pressure causes piston 18 
to rise. 



G-G Brake Valve, rEcuLiAiuTiEs and Troubles 173 

Q. Where could this leak be? 

A. In the little drum itself; in the pipe leading to it; 
in the pipe leading to the black hand on the gauge; gasket 
32 leaking so as to allow little-drum pressure to escape to the 
atmosjohere; a scratch on the rotary seat between the prelim- 
inary exhaust port e and the groove li leading to the atmo- 
sphere. 

Q. Why does it leak on lap and not on running or full 
release position? 

A. Because the leak is not fed on lap^ as all ports are 
closed^ but it is in the other two positions. 

Q. If the two hands on the gage do not show the same 
pressure when the valve is left in full release position, 
what is the trouble? 

A. The gauge is incorrect. The main reservoir and brake- 
pipe being directly connected in this position both gauge 
hands should show the same pressure. 

Q. What could be the trouble if in running position 
the red hand showed seventy and the black ninety 
pounds? 

A. The gauge pipes have been connected to the wrong 
hands. 

Q. What should be done if piston 18 does not respond 
readily to reductions and seems to stick? 

A. The piston sliould be removed and cleaned; but never 
remove the packing ring 19, as it may be sprung or broken. 

Get the ring to work free by using kerosene oil to clean 
it. 

Q. How would you apply the brakes if the preliminary 
exhaust port were closed and no reduction could be made 
in service position? 

A. Go carefully toward the emergency position; or it 
might be done by lapping the valve and unscrewing the 



174 Aie-Brake Catechism 

nut a little that connects the pipe leading from the little dram 
to the brake valve until the desired reduction was obtained. 



DUPLEX MAIX-EESEEYOIE EEGULATIOX. 

AS USED WITH ALL STAXDARD V^'ESTIXGIIOUSE EQUIPMEXTS. 

Q. What is the special object to be obtained with the 
arrangement shown in Figs. 54, 55, and 56? 

A. To provide a means by which a high main-reservoir 
pressure can be obtained with which to release the brakes and 
recharge, without its being necessary for the pump to oper- 
ate against this high pressure except during only such tune 
as the brakes are applied. 

Q. Of what does the duplex governor consist? 
A. Of two pressure-regulating heads which operate in 
conjunction with one steam portion of the governor. 

Q. What are the two pressure regulating heads called? 

A. The shorter one is called the '^excess-pressure^^ head; 
the other is called the ^^maximum-pressure'^ head. 

Q. How is the governor connected to the G-6 brake 
valve? 

A. Eeferring to Fig. 54, the maximum-pressure head is 
connected to the pipe which connects main-reservoir pres- 
sure in the brake valve to the red hand of the duplex air 
gauge; the lower part of the excess-pressure head is connected 
to a special port in tlie brake valve; the upper connection of 
the excess-pressure head is piped to the brake-pipe just below 
the brake valve. 

Q. At what pressure is it customary to adjust the pres- 
sure heads? 

A. The excess-pressure head is adjusted to stop the pump 



Duplex Mai^-IIeservoir EEGULATioisr 



175 




o 

< 

o 



o 



< 
w 

P 

Q 

a 

P 
O 

w 

M 

H 
W 



C 






176 



Air-Brake Catechism 



when main-reservoir pressure is 20 pounds above the regula- 
tion of the feed valve^ and the maximum-pressure head is 
adjusted at 130 or 140 pounds. 

Q. If the brake valve handle is in full release or run- 
ning position, how much pressure will there be in the 
main reservoir when the pump is stopped; if in any of 
the* other positions what pressure results? 

A. If the feed valve is set for 70 pounds^ 90 pounds main- 
reservoir pressure is obtained when the brake valve is in re- 
lease or running positions; in the other positions 130 or 140 
pounds is obtained. 





l> Pipe Tap A 



Connect A to L. P. i^^ 
Gov. Head. 



Fig. 56. 



Q. What objection is there to the use of one pump gov- 
ernor adjusted to shut off steam from the pump when a 
main reservoir pressure of 140 pounds is obtained? 

A. A pump operating against a high pressure continu- 
ously will wear faster and is much more likely to become 
overheated in freight service. 

Q. Explain why the pump is stopped when the main- 
reservoir pressure is 20 pounds above feed-valve regula- 
tion, if the brake-valve handle is in release or running 
position. 

A. As indicated on Fig. 54, the pipe leading to the lowej 
part of tlie excess pressure head is connected at tlie brake 
valve to a hole drilled into the port^ which, in running posi- 



Duplex Maix-Eeservoir EEGULATioisr 177 

tion, conveys air to the feed valve. This port contains main- 
reservoir pressure^ witli the brake valve in this position. The 
upper part of the excess-pressure head, as already stated, con- 
nects with the brake-pipe below the brake valve. As soon 
as main-reservoir pressure reaches a point that is 20 pounds 
above brake-pipe pressure, the pump is stoj)ped. 

Q. Why is a higher main-reservoir pressure obtained 
with the brake valve in other than release and running 
positions? 

A. When the brake-valve handle is moved toward service 
position, the port supplying main-reservoir pressure to the 
feed valve is closed^ and the air which escapes at the gover- 
nor vent port causes the pump to start. It will not cease 
operation unless the valve handle is again moved to run- 
ning or release position, until sufficient pressure has been 
accumulated in the main reservoir to operate the maximum- 
pressure head^ usually adjusted for 140 pounds. Air from 
the main reservoir enters the brake-valve as indicated and 
passes through pipe A to the maximum-pressure governor 
head. 

Q. Are all G-6 brake-valves drilled so that the pipe 
from the excess-pressure head can be connected into the 
port leading to the feed valve? 

A. All are that have been put in service recently. Figs. 
55 and 56 indicate the proper location for this hole in case 
it is desirable to install the duplex governor in connection 
with the old standard equipment still using the single gov- 
ernor. 



CHAPTER VI. 

WESTINGHOUSE OLD-STYLE HIGH-SPEED 

BRAKES 

Q. What does Fig. 57-A on page 182 represent? 

A. The old-stj'le Westingliouse High-Speed brake. 

Q. Why was the introduction of the high-speed brake 
necessary? 

A. The call by the traveling public for higher train speed 
rendered it necessary to insure safety of lives and property. 

Q. What class of trains use this brake? 

A. It is being introduced very generally in both local 
and through joassenger train service on the principal trunk 
lines. 

Q. What percentage of braking power to the light 
weight of a passenger car is generally used with the ordi- 
nary quick-action brake? 

A. Eighty per cent, on 50 lbs. cylinder pressure. 

Q. What percentage is used with the high-speed 
brake? 

A. About one hundred and thirty per cent, if the cylinder 
pressure is figured as 8G pounds^ and eighty per cent, with 
a 50-pound cylinder pressure. With the "U^ triple and a 
brake-pipe pressure of 110 pounds, the percentage of braking 
power in emergency applications is 190. 

Q. Why is it safe to use a higher braking power on 
wheels when the train is running fast? 

A. Because the faster tlie wheels turn, tlie greater is 



Old Style High Speed Brake 179 

the inertia of the wheels^ which the friction of the brake 
shoes has to overcome before they will cease revolving. The 
Westinghouse-Galton tests^ made in England^ in 1878^ proved 
that the faster the tread of the wheel moved against the 
brake shoe^ the less the friction between the two. As the 
speed decreases the friction increases^ the friction between 
the wlieel and the rail remaining about constant^ regardless 
of the speed of the train. 

Q. What brake-pipe and auxiliary-reservoir pressures 
are carried with the high-speed brake? 

A. One hundred and ten pounds. 

Q. At what pressure do the auxiliary-reservoir and 
brake cylinder equalize when the brake is fully set in 
emergency, using one hundred and ten pounds auxiliary- 
reservoir pressure? 

A. About eighty-six pounds. 

Q. What reduces this eighty-six pounds to sixty 
pounds, the safe pressure for slow speeds? 

A. The automatic reducing valve shown in the accom- 
panying cut (Fig. 57). 

Q. Explain the action of the reducing valve. 

A. When air is in the brake cylinder it is free to reach 
the top of piston 4 of the reducing valve. 

As long as the tension of the spring 11 is greater than the 
brake-c}dinder pressure on top of the piston, the slide valve 
8 remains in the position shown. 

When the brake is fully set, the pressure in the C3dinder 
being greater than the tension of the spring, the piston 4 
is forced down and carries the slide valve with it, thus open- 
ing port h into port a, allowing brake-cylinder pressure to es- 
cape to the atmosphere. 

The apex of the triangular port h points up. If the slide 
valve 8 is drawn down a little, as in a service application, port 
h has a wide opening into port a, allowing cylinder pressure 



180 



Air-BpvAke Catechism 




1/2 PIPE TAP W^ TO BRAKE CYLINDER 



YiQ, 57. — High-Speed Automatic Reducing Valve. 

to escape quickly. The high cylinder pressure in emergency 
forces piston 4 down full stroke, and cylinder pressure es- 
capes slowly through the small end of port h. As cylinder 
pressure lessens, spring 11 raises piston 4 and slide valve 8, 



Old Style High Speed Brake 181 

opening port h wider^ thus releasing air faster; the slow ex- 
haust ensues with a high^ and quick exhaust witli low train 
speeds. Spring 11 is adjusted to sixty pounds on passenger 
cars and sixty on engines and tenders. 

Q. What is necessary to make a high-speed brake out 
of the ordinary quick-action passenger-car equipment? 

A. Simply the addition of the reducing valve. 

Q. What change has to be made on engines? 

A. Two feed valves are used^ being fastened to a revers- 
ing-cock which is piped to a rcversing-coch pipe bracket, the 
latter replacing the feed valve on the G-6 brake value^ and re- 
ducing valves are connected to the tender and driver brake 
cylinders. If an old style single pump governor is installed, 
it must be replaced by the new duplex pump governor. 

Q. Why are two feed valves used? 

A,. Only one is used at a time. They are so arranged 
that the engine may be used with the ^^high-speed^^ brake 
or with the ordinary quick-action brake. 

Q. At the same speeds, in how much less distance can 
a stop be made with the High-Speed than with the ordi- 
nary Quick- Action Brake? 

A. About 33 per cent. 

Q. With an auxiliary-reservoir pressure of 110 pounds, 
is a higher cylinder pressure developed than when 70 
pounds is used if a 5, 10 or 15-pound service reduction 
of brake-pipe pressure is made? 

A. With the customary piston travel of from six to eight 
inches the same cylinder pressure would result in either case. 

Q. Would the cylinder pressure developed be the same 
with a gradual break-pipe reduction of 24 pounds? 

A. No^ the cylinder pressure would be greater when us- 
ing a brake-pipe pressure of 110 pounds. 



182 




fa t^ 

o o* 

o a 

H a 



P 
I 

d 



Old Style High Speed Brake 183 

Q. Give a rule which covers this point. 

A. As long as brake-pipe reductions are not continued 
after the equalization point between the cylinder and reser- 
voir when the 70-pound train-line pressure has been reached, 
the same cylinder pressure will result in either case. If, how- 
ever^ the reductions are continued beyond this pointy a gain 
is made when using the higher pressure, and it can be raised 
until such time as the High-Speed Eeducing Valve operates 
to discharge air to the atmosphere. 

Q. Why is it that the cylinder pressure would be the 
same in either case with a service reduction of 10 pounds 
when employing either a 70 or 110-pound pressure? 

A. By making the proper calculations it will be found 
that in either case the same number of cubic inches of free 
air has passed to the brake cylinder. In other words, the 
same number of cubic feet of free air are used by reducing 
the auxiliary-reservoir pressure from 70 to 60 as from 110 
to 100 pounds. 

A 20-pound reduction, using a 70-pound brake-pipe pres- 
sure, would equalize the reservoir and cylinder pressures at 50 
pounds with an 8-inch piston travel; using the 110-pound 
brake-pipe pressure and making a 20-pound reduction would 
give a cylinder pressure of 50 pounds, but there would still 
be 90 pounds in the auxiliary-reservoir; hence, with a fur- 
ther reduction of brake-pipe pressure the triple valve would 
permit more reservoir pressure to pass to the brake cylinder 
thus increasing its pressure. 

Q. Do the brakes apply any quicker in service with 
the High-Speed than with the Quick- Action Brake? 

A. Yes. 

Q. Explain the answer to the last question. 

A. On account of the higher pressure used the air passes 
through the ports quicker from the auxiliary reservoir to the 



184 



Aik-Brake Catechism 



brake cylinder. Practically the same effect is "produced as is 
done by increasing the boiler pressure of an engine, which 
added pressure produces a corresponding quickness of action. 



TO BRAKE 



CYLINDER 




position of ports 
emergency stop 

Fig 




POSITION OFPORTS^ 
SERVICE STOP 
PRESSURE EXCEEDING 60 POUND! 
IN BRAKE CYLINDER 

Fig. 59. 



POSITION OFPORTS^ 
RELEASE 

Fig. 60. 



It is this quickness of action wliich has created the general 
impression that a light reduction of brake-pipe pressure i^ro- 
duces a greater cylinder pressure when using a 110-pound in- 
stead of a 70-pound pressure. This is a mistaken idea, ex- 
cept as there might be a very slight difference because of 



Old Style High Speed Brake 185 

the piston moving out and closing the leakage groove quicker 
with the high than with the low pressure. 

Q. Which method produces the best results in making 
station stops with the High-Speed Brake? 

A. The two application method^ the same as should be used 
when employing the 70-pound brake-pipe pressure. 

Q. If, when using the 110-pound brake-pipe pressure, 
a sudden reduction of pressure is made and the brake- 
valve handle is returned to lap, at what pressure will 
the brake-pipe, auxiliary-reservoir and brake cylinder 
equalize? 

A. iVpproximately 86 pounds. 

Q. The triple valve is now in emergency position and 
the auxiliary-reservoir and cylinder pressures are escap- 
ing to the atmosphere through the reducing valve, which 
closes when the pressure in it has been depleted to 60 
pounds. The brake-pipe pressure is still approximately 
85 pounds; will this pressure not force the triple piston 
to release position and release the break entirely? 

A. 'No; as soon as the reservoir pressure is slightly less 
than the brake-pipe pressure^ plus the tension of the grad- 
uating springs the triple piston is forced to lap position^ in 
which position no more reservoir pressure can reach the 
brake cylinder. The reducing valve continues to reduce cylin- 
der pressure until it closes when this pressure has reached 
60 pounds. 

A corresponding action takes place in response to a grad- 
ual and heavy brake-pipe reduction., sufficient to cause the 
reducing valve to open and the triple piston to move to emer- 
gency position and compress the graduating spring. 

Q. Is the cylinder pressure reduced to 60 pounds un- 
der these conditions? 

A. Yes, 



186 



Air-Brake Catechism 







5 

o 

H 

Q 

W . 

M 

2 3 

o 
o 

1^ 

52; 



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W 

C/2 



<x> 

M 



V^'k.^- 



Old Style High Speed Brake 187 

Q. What is a great advantage of the High-Speed 
Brake other than those already outlined? 

A. Two full service reductions of 20 pounds and releases 
can be made without requiring any recharge of the auxiliary 
reservoir and there will still be 70 pounds pressure available 
with which to stop, if necessary. 

Q. How often should the High-Speed Reducing Valve 
be cleaned? 

A. Once a year when used on cars^ and once in six months 
when used on engines and tenders. 

Q. What kind of oil should be used for lubricating 
purposes? 

A. A high grade mineral oil. 

Q. How can a High-Speed Reducing Valve be taken 
apart so that it can be put together without changing the 
adjustment of the regulating spring? 

A. Do not remove the cap nut. The lower case can be 
removed and replaced without disturbing this part of the 
mechanism. 

Q. If the braking power on a car is designed for 80 
per cent, of its light weight when using a brake-pipe pres- 
sure of 70 pounds, what braking power will be developed 
with an emergency application of the High-Speed Brake 
at the moment of maximum cylinder pressure? 

A. Approximately 130 per cent. 

The cut (Fig. 62) gives an idea of the advancement in* air- 
brake appliances. The figures represent, by scale^ stops made 
by trains going at the same rate of speedy but equipped as 
indicated. 

It takes about twice as far to stop a train going at forty^ 
three times going at fifty^ and about five times going at 
sixty miles an hour, as it does if the speed of the train is 
thirty miles an hour with the Quick-Action Brake. 



188 



Air-Beake Catechism 



Comparative Stops Made With High-Speed and Quick- 

AcTiox Brakes. 



>eed. 


stop in 
High-Speed. 


Feet. 

Quick Action. 


Quick Action 

Per Cent. Less 

Efficient. 


Foot in Favoi 

ot'Higli-Speeil 

Brake. 


45 


560 


710 


26.8 


150 


50 


'roo 


880 


24.8 


175 


60 


1063 


1360 


28.3 


300 


70 


1560 


2020 


29.5 


460 


80 


2240 


2780 


24.1 


540 



Brake-pipe pressure used with High-Speed Brake, 110 
pounds. 

Brake-pipe pressure used with Quick-x\ction Brake, TO 
pounds. 

The above table refers to stops made with chilled cast-iron 
wheels and soft cast-iron shoes with a train which was sup- 
posed to represent average conditions of service. 



Hand Brake 



Straisrht Air 

1869 

Plain Automatic 
1872 

Quick Action Automatic 
1887 

Hifi^h-Speed Brake- 
1894 

New TYDe"L" Equipment 
1908 

New Type "L" Equipment 
1308 



80 LBS. IB. P.P. 



110 LBS. B.P.P. 
! L 



500 



1000 1500 2000 2500 
LENGTH OF STOP - FEET 



3000 



Fig. 62. — Progress of Air Brake Efftctexcy as Siiowx by Com- 
parative Distances ijx which Trains are Stopped. 



Double Pressure Control Equipment 189 

DOUBLE PEESSUEE CONTEOL EQUIPMENT OE 

SCHEDULE U. 

Q. What does Fig. 62-A on page 190 represent? 

A. The Double-Pressure Control or Schedule U Equip- 
ment sometimes used on freight engines. 

Q. How does it differ from the old style high-speed en- 
gine equipment? 

A. Instead of high-speed reducing valves^ a safety valve 
is placed in the tender brake cjdinder head, and another in 
the pipe between the driver-brake triple valve and cylinders. 

Q. What is the object of this special equipment? 

A. It is designed for special use on roads having heavy 
grades and handling loads^ such as ore^ down the grade, and 
empty cars up. 

Q. What special advantage is gained? 

A. By using two feed valves which are usually set for 
70 and 90 pounds^ either one of these pressures can be used 
in the brake-pipe and 90 or 110 pounds can be used in the 
main reservoir, when the brake-valve handle is in release or 
running positions. 

Q. Would there not be danger of sliding wheels if 90 
pounds were used as brake-pipe pressure? 

A. Possibly if used on empty cars ; but if used on heavily 
loaded cars, there would be no danger, as the highest possible 
braking power is usually 70 to 80 per cent, of the light 
weight of the car, and when loaded to its full capacity, the 
percentage of braking power, as compared with the combined 
weight of the car and its contents, is much smaller than 
this, even when using a brake-pipe pressure of 90 pounds. 

Q. How much more powerful would a brake be when 



190 




Double Pressure Control E'quipment 191 

using a brake-pipe pressure of 90 pounds as compared 
with 70? 

A. Approximately 25 per cent. 

Q. With the cocks as shown in Fig*. 62-A, which feed 
valve is operative? 

A. The 70-pound feed valve. 

Q. What benefit is derived from this device when the 
70-pound feed valve is cut in? 

A. With the brake valve in running position^ the pump 
does not have to work against a higher pressure than 90 
pounds^ but just as soon as the brakes are applied the pump 
raises the pressure in the main reservoir to 110 pounds^ which 
pressure is very helpful to insure a quick release on a long 
train and quickly recharge the auxiliaries. 

Q. What would be done in case the cars were all heav- 
ily loaded and it was desired to use a brake-pipe pressure 
of 90 pounds and a minimum main-reservoir pressure of 
110 pounds? 

A. The reversing-cock handle would be moved so as to 
cut out the 70-pound feed valve and cut in the 90-pound feed 
valve. 

Q. Would it be safe to use the 90-pound brake-pipe 
pressure when there were air brakes on both light and 
loaded cars in operation in the same train? 

A. While there is a chance ihat a little wheel sliding might 
result if an emergency or very heavy service reduction were 
made^ the likelihood of serious sliding is so slight that it is 
not customary to cut out empty cars and thus lose their brak- 
ing power. 

Q. When using a 90-pound brake-pipe pressure, is the 
same brake-pipe reduction necessary to apply the brakes 
in full as is used with a 70-pound brake-pipe pressure? 

A. No ; a heavier reduction would be necessary. 



l'^:d 



Air-Brake Catechis:m 



Q. How much of a brake-pipe reduction would equalize 
the auxiliary-reservoir and brake-cylinder pressures, 
using an initial pressure of 90 pounds? 

A. About 27 pounds, if the piston travel were approximate- 
I3' eight inches. 




3-4 



^'t 




Fig. 63. — Old Style Safety 
Valve. 



Fig. 64. — New Style Satei 
Valve. 



Q. Why are safety valves placed upon the tender, 
driver, and truck brakes? 

A. So as to allow all pressure over 50 pounds to escape 
to the atmosphere. Experience shows that over-heating of 
tires is likely to ensue if a greater pressure than this is used 
on the tender, driver or truck brakes. 



Combined Automatic and Straight Air 193 
> 

Q. What is best to use on the engine if the grade is 
very long and heavy and the speed slow? 

A, A water brake. With this brake no heating of tires is 
produced, as the braking is done with the pistons in the main 
cylinders. 

Q. With a brake-pipe pressure of 90 pounds, is any 
more braking power developed with a 5, 10 or 15-pound 
service reduction than if 70 pounds was carried on the 
brake-pipe? 

A. 'No; no gain will be made unless brake-pipe reduc- 
tions are continued after the point has been reached at which 
the reservoir and brake cjdinder pressures would equalize when 
using the 70-pound brake-pipe pressure. 

Q. Why is this? 

A. Because^ if calculated, it will be found that it re- 
quires tfhe same number of cubic inches of free air to raise 
the auxiliary-reservoir pressure from 50 to 70, 70 to 90, or 
200 to 220 pounds. If the same amount of air is used in each 
case, the same pressure would result if 20 pounds were taken 
from the auxiliary, when containing any pressure above 70 
pounds, and j)ut into the brake cylinder if the piston travel 
were not less than 8 inches. 

WESTINGHOUSE OLD-STYLE COMBINED AUTOMA- 
TIC AND STRAIGHT AIK-BRAKE EQUIP- 
MENT FOR ENGINES AND TENDERS. 

Q. For what purpose was this equipment designed? 

A. For use on engines and tenders in yard and freight 
service. 

Q. Why is it necessary on yard engines with old style 
equipment? 

A. Because an old-style triple valve will not recharge the 



194 




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Combined Automatic and Straight Air 195 

auxiliary-reservoir between very frequent brake applications; 
as a result it is necessary for the engineer to make a great 
many stops with the reverse lever. Eeversing an engine tends 
to draw cinders into the cylinders^ where they cut the cylind- 
ers and packing. The brake on a switch engine should be 
such that it can be used as often as desirable and always have 
the maximum power available. Using the brake constantly 
also keeps the tires in much better condition. A quick re- 
lease is possible with the straight air and^ if desired, the 
brake can be partially released. 

Q. Of what use is it on road engines with old style 
equipment? 

A. Aside from the advantages stated above^ w^hile switch- 
ing, it provides a means of bunching slack^ permits slow-ups 
to be made to pick up a flag, can be used, if desired^ to help 
retard the speed of the train while recharging on descending 
grades ; also in slowing up at times when much braking power 
is not required^ and where it is unnecessary to waste the air 
to apply the brakes on all the cars and thus put needless work 
upon the pump ; and it can be used to meet many similar con- 
ditions encountered in road service. 

Q. Does this brake operate entirely separate from the 
automatic, and is there no danger of obtaining too much 
braking power if one is used without fxrst releasing the 
other? 

A. Each is entirely independent of the other, and the 
safety valves placed in the pipes leading to the driver and 
tender brake cylinders will permit only the predetermined 
amount of pressure considered suitable for maximum braking 
power. 

Q. What are the parts necessary to add to the standard 
engine and tender equipment? 

A. As illustrated in Fig. 64-A, it is necessary to apply on 



196 



Air-Brake Catechism 



the engine a Slide-Valve Eeducing- Valve, a %" Straight-Air 
Brake Valve^ a Safety Valve set at 53 pounds^ and a double 
check valve. On the tender the additional parts consist of 
a double check valve, a safety valve set at 53 pounds, and 
suitable hose and connections. 

Q. What is the object of the Slide-Valve Reducing 
Valve? 

A. To reduce main-reservoir pressure to 45 pounds, that 
being considered proper with the straight-air brake. 



1 PIPE 
2 
COTRIPLe VALVE ..^ry^^a 




Pipe 



STRAIGHT Aia 
BRAKE VALVE 



Fig. 65. — Double Check Valve. 



Q. What positions has the Straight- Air Valve? 

A. Eelease, application and lap positions. In release posi- 
tion^ cylinder pressure is exhausted directl}^ to the atmo- 
sphere ; in application position main-reservoir pressure, reduc- 
ed to 45 pounds, passes tlirough the brake valve to the doubL 
check valves and thence to the cylinders. 

Q. Explain the mechanism of the double check valv( 
(Fig. 65). 

A. It consists of a double piston witli a leatlier face oi] 
each end. Wlien air comes from the triple valve it force 
the pistons to such a position that no air can enter througl] 



IB. 



Combined Automatic and Straight Air 197 

the straight-air pipe; a set of ports is also opened to permit 
the air coming from the triple valve to flow to the brake 
cylinder. When the straight-air is used the opposite effects 
are produced; that is, the pistons blank the port connection 
to the triple valve and open a port connection from the 
straight-air pipe to the cylinder. 

Q. What is the object of the safety valve (Fig. 64-A)? 

A. If the reducing valve did not reduce the pressure prop- 
erly, owing to its being in poor condition, or if the automatic 
brake were used without first releasing the straight-air brake, 
the safety valve would allow any pressure in excess of 53 
pounds to escape. 

Q. If the straight-air brake is left partially applied 
and the automatic is then applied, what will be the result? 

A. JSTothing unusual will be noticed until the engineer 
tries to release the automatic, at which time, as soon as the 
pressure in the pipe between the triple and double check 
valve is less than that between the straight-air valve and 
double check valve, the piston in the double check valve wall 
move over so as to stop the escape of air through the triple 
and establish a connection between the straight-air valve and 
cylinder. 

Q. How then may the brakes be released? 

A. By placing the straight-air valve in release position, 
where it should always be when the automatic brake is in use. 

Q. Where should the handle of the Engineer's Brake 
valve be placed when the straight-air is in use? 

A. In Eunning Position. 

Q. If the automatic brake is partially applied and the 
straight-air is then used, what will be the result? 

A. As just described, with the opposite conditions, the 
brake could not be entirely released on the engine and tender 



198 Air-Bkake Catechism 

without putting tlie Engineer's Brake Valve 6i the automatic 
system in Running or Eelease Position. 

The following directions^ if properly followed^ will pro- 
duce best results : 

1. Always keep both brakes cut in and ready for opera- 
tion, unless failure of some part requires cutting out. 

2. Always carry an excess pressure in the main reservoir, 
as this is necessary to insure a uniformly satisfactory oper- 
ation. 

3. When using automatic, keep straight-air brake valve in 
release position, and when using straight-air. keep the auto- 
matic valve in running position; this to avoid sticking of the 
driver and tender brakes. 

4. Automatic must not be used while straight-air is ap- 
plied; if desirous of using the automatic, first release the 
straight-air. 

5. Though the use of straight-air while automatic is ap- 
plied will not increase the driver and tender brake cylinder 
pressure above 45 pounds, yet release of either cannot be 
assured while the other brake valve is on lap or application 
position. 

G. Bear in mind that the straight-air on the driver and 
tender brakes is almost as powerful as the automatic brakes 
on same, and that each should be used with care to avoid 
rough handling of the train, or in holding down long grades, 
loosenin<2: of tires on drivers. 

7. The straight-air reducing valve should be kept adjusted 
to 45 pounds and the driver and tender safety valves at 53 
pounds. Where a full application of the straight-air causes 
cither or both safety valves to operate, it indicates too high 
adjustment of reducing valve or too low adjustment of safety 
valves. Have them tested and adjusted. 



Combined Automatic axd Straight Air 19,9 
Straight-Air Brake Valve. 

Q. What is the valve shown in Figs. 66, 67, 68, 69 and 
70, and with what is it used? 

A. It is known as the Straight-Air Brake Valve; it is 
the valve used in connection with the Combined Automatic 
and Straight-Air Brake. 

Q. What do the different views represent? 

A. Fig, 68; a side view of the outside of the valve; the 




To Main Reservoir 



•^ 



3 Y ^2 

Fig. 66. Fig. 67. 

Stkaight-Air Bkake Valve. 



\x 

Double 
Check Vdlwc 



200 



Air-Brake Catechism 



view (Fig. 70) is a horizontal cross-section " tlirougli FF 
(Fig. 68); Fig. 69 is a vertical cross-section; Fig. ^Q, an 
end section showing the valve that controls the flow of pres- 
sure coming from the main reservoir; and Fig. 67 is an end 




\2 






Fig. 68. Fig. 69. 

Steaight-Air Brake Valve. 

section through a plane whieli permits the valve controlling 
the exhaust to be seen. 

Q. Name the different parts of che valve. 

A. 1 is tlie valve body; 2, tlie valve shaft; 3, one of the 
two tappet pieces held to the shaft by rivets; 4, the handle; 



Combined Automatic and Straight Air 201 

5, the quadrant; 6, the shaft washer, which is of leather; 7^ 
tiie shaft springy which liolds tlie collar of the shaft against 
the leather washer, thus making an air-tight joint; 8, the 
valve which controls main reservoir pressure; 9, the one 
controlling the escape of air to the atmosphere from the brake 
cylinder; 10 and 11, the check valve springs; 12 and 13, the 
valve caps; 14, the shaft cap nut; 15, the handle screw; 16, 
the handle latch; and 17, the latch spring. 

Q. The valves 8 and 9 control the flow of air through 
the brake valve; how are these valves controlled? 

A. By the handle 4 acting through the shaft 2. As the 
handle is moved the shaft starts to rotate, thus causing one 
of the tappet pieces 3 (Figs. 66 and 67) to engage the stem 
of either valve 8 or 9, according to the direction in which 
handle 4 is moved. If moved to the right (Fig. 66) valve 
8 is unseated; if moved to the left valve 9 (Fig. 67) is un- 
seated. The shaft, as shown in Figs. 66^ 67 and 69, is cut 
away in two places, at the bottom of each of the slots a 
tappet piece is fastened with two rivets. 

Q. What is the object of the tappet piece? 

A. The shaft could be designed to come in contact with 
the valve stems, but the steel tappet pieces present a better 
wearing surface, as do alpio the steel pins inserted at the top 
of the stems of valves 8 and 9 (Fig. 69). 

Q. Where is the Straight- Air Brake Valve usually 
located? 

A. On the side of the cab within convenient reach of the 
engineer. Sometimes on certain few classes of engines, it 
is more convenient to locate it on the boiler head. 

Q. In what three positions may the handle of the valve 
be placed? 

A. Kelease, application and lap. 



202 Air-Brake Catechism 

Q. Explain these positions. 

A. As shown in Fig. 67 it is on lap; moved to the right 
it is in application or service position; and to the left it is in 
release position. 

Q. Can the brakes be applied gradually and released 
gradually with this brake valve? 

A. Yes; a quick release or application is obtained when 
the valve handle is moved to either of the extreme positions 
shown. To obtain a gradual effect the handle of the valve 
should be moved a distance not sufficient to obtain the full 
movement of the valves. This can be told by the feeling 
when applying the brake, and by the sound as well as the 
feeling when making a release. 

Q. What connections has the brake valve? 

A. It has three and^ as indicated^ they connect with the 
main reservoir at W; the brake pipe^ or the one leading to 
the double check valve, at X (Fig. 67) ; and to the exhaust 
at Y. 

Q. Explain the passage of air through the brake valve 
when the handle is placed in application position. 

A. When the valve handle is moved to the right the 
tappet piece in the shaft engages the stem of valve 8^ forcing 
the valve from its seat against the pressure beneath it and 
the tension of spring 11. Air which comes from the main 
reservoir through the reducing valve (Fig. 64- A) enters 
the brake valve at W (Fig. GG) and passes up by the un- 
seated valve 8 into chamber h, thence through port V (Fig. 
69) into chamber h^ and out at X (Fig. 67) into the pipe 
which leads to the double check valves (Fig. 64:-A), and 
through these valves to the brake cylinders. 

Q. When the valve handle is moved to lap, after suf- 
ficient braking power has been obtained, what closes valve 
8 on its seat? 



Combined Automatic and Straight Air 203 

A. In this position the stem of valve 8 is clear of the 
tappet piece attached to the shaft, and the spring 11, together 
with the pressure in chamber a, forces the valve to its seat. 

Q. What part has valve 9 performed during the opera- 
tions just described? 

A. Spring 10 (Fig. 67), together with the pressure in 
chamber h", forces valve 9 to its seat and it thus prevents the 
escape of air to the atmosphere. 

Q. Explain the passage of the air when the brake valve 
handle 4 is placed in release position. 

A. Valve 9 is forced from its seat and air from the brake 
cylinder comes back through the double check valves (Fig. 
61:-A), enters at X (Fig. 67) into chamber h^, passes by the 
unseated valve 9 into chamber c, thence to the atmosphere at 
Yj and thus releases the air from the brake cylinders. 

Q. If the brake valve handle is left in application posi- 
tion how much pressure will be obtained in the brake 
cylinder? 

A. The reducing valve between the main reservoir and 
brake valve is adjusted to close when the pressure between 
the reducing valve and brake valve is 45 pounds, hence this 
is the maximum pressure that can be obtained in the brake 
cylinders when using the straight-air brake. 

Q. In what position should the brake valve handle be 
carried when the brake is not in use? 

A. Kelease position; so placed any slight leakage of main- 
reservoir pressure by the seat of valve 8 (Fig. Q^) can not 
creep on the brakes, since the air would escape direct to the 
atmosphere by the unseated valve 9. 

Q. In piping this valve how may mistakes be avoided? 

A. By examining the raised letters cast on the outside of 
the lugs into which the pipes are screwed. M. E. indicates 
main reservoir; EX., the exhaust, and T. P., the brake-pipe 



204 Air-Brake Catechism 

connection, or the one through which air reaches the brake 
cylinders after passing through the double check valves. 

Peculiarities and Care of the Straight-Air Brake 

Valve. 

Q. What are the only parts in the Straight-Air Brake 
Valve that get out of order? 

A. The rubber seats of valves 8 and 9^ and the shaft 
washer, 6. 

Q. How may the check valves 8 and 9 be removed? 

A. By removing cajos 12 and 13 the valves will fall out. 

Q. Are valves 8 and 9 interchangeable? 
A. Yes. 

Q. What effect would be produced by a leak across the 
seat of valve 8? 

A. With the brake valve in release position a constant 
blow would exist at the exhaust. AVlien the brake was ap- 
plied this leak would continue to apply the brakes harder. 

Q. What effect would be produced by a leak across the 
seat of valve 9? 

A. After the brake was applied and the brake-valve handle 
placed on lap the leak would gradually release the brake. 

Q. What effect would be produced if gasket 6 (Fig. 
69) formed a poor joint? 

A. The bad effect of this would only be noticed during 
such time as the brake was applied, when air chamber b, con- 
nected through port h^ and b^ with the pipe leading to the 
double check valves and brake cylinders, would pass by gas- 
ket 6 and escape to the atmosphere, causing a blow at the ex- 
haust and at the handle end of the shaft, tending to release 
the brake. 



Combined Automatic and Straight Air 205 

Q. To remove the shaft 2 for the purpose of cleaning, 
or for renewing gasket 6, what should first be done? 

A. First remove valves 8 and 9 to avoid bending stems of 
these valves wliich^ as shown in Fig. 69, extend within the 
circumference of the shaft 2. Next, remove the handle 4 and 
cap 14, and the shaft can be lifted out. 

Q. In cleaning the valve what special care should be 
taken? 

A. Not to put any oil on valves 8 and 9, or where it can 
work down upon the seats. 



CHAPTER VII. 

THE WESTINGHOUSE No. 6 ET LOCO- 
MOTIVE BRAKE EQUIPMENT 

The first Westingliouse ET Locomotive Brake Equipment 
to come into general use is now designated as the ^o. 5 Equip- 
ment, and was described in the 1907 edition of this book. It 
has since been succeeded by the No. 6 Equipment described 
below. The principal differences between the two equipments 
are mentioned at the end of this chapter^ page 258. 

Q. What does the symbol ET designate? 

A. It designates the Westingliouse improved engine and 
tender, or locomotive, brake equipment, the letters ET being 
the initials of the words ^^Engine'^ and ^^Tender.^^ 

Q. In what respect is the ET locomotive equipment an 
improvement over the standard brake? 

A. In that it consists of fewer parts; that is, it combines 
practically in one mechanism the present combined-auto- 
matic and straight-air brake ; and it possesses many improved 
features in operation. It is easier to understand and to 
operate and is cheaper to maintain than the present type of 
combined-automatic and straight-air brake. 

Q. What parts of the present combined-automatic and 
straight-air brake are displaced by the ET brake? 

A. All triple valves, all auxiliary reservoirs, all pressure 
retaining valves, all high-speed reducing valves, one brake- 




^3 
:3 



s 

o 

o 

o 



o 
U 



C 



o 



CO 

6 
g 

5 

Ph 



I 






ET Locomotive Brake Equipment 207 

pipe feed valve^ the reversing cock^ and all double check 
valves. 

Q. What does Fig. 71 represent? 

A. It represents all the parts of the ET equipment, and 
shows the method of piping them together. 

Q. What are the principal parts of the ET equipment? 

A. Eeferring to Fig. 71, it will be seen that they are; an 
air pump, the main reservoirs, a main-reservoir cut-out cock, 
an automatic brake valve, an independent brake valve, a du- 
plex pump governor, a distributing valve, a brake-pipe feed 
valve, a reducing valve, and the necessary piping, cut-out 
cocks, brake C3dinders,, brake-pipe strainers, angle cocks, and 
pressure gauges. 

Q. Can the ET equipment be used in all kinds of 
service, such as high-speed passenger, in freight, and in 
switching without change or modification of its parts? 

A. Yes; it is an equipment suitable for any kind of 
engine and train service, and engines equipped with it may 
be used in the different kinds of service without change or 
modification of its parts. 

Q. Why is this improved equipment necessary? 

A. Because of the heavier weight of all kinds of modern 
locomotives, greater weight and speed of passenger trains, 
greater length of freight trains, there is need of a more posi- 
tive and more flexible brake than the present standard to 
control their motion. There is also need of a means of 
graduating at will both the application and the release of 
the locomotive brake as well as releasing the brakes simultane- 
ously with, or independently of, the train brakes; this may 
be done with the ET brake. 

Q. Can shorter and smoother stops be made with trains 
that are hauled by locomotives equipped with this brake 



208 Air-Brake Catechism 

than can be made with those hauled by locomotives hav 
ing the older type? 

A. Yes; considerably shorter and smoother stops can be 
made. Shorter because the distributing valve automatically 
maintains the pressure in the Ijrake cylinders against leakage, 
during an application, and smoother because of the flexibility 
and quick response of locomotive brakes by means of the 
independent brake valve, and the graduated release feature in 
connection with the automatic brake valve. It also srives 
30 per cent, more braking power in an emergency applica- 
tion. 

Q. What other special advantage is obtained by the 
use of this equipment? 

A. Brakes on long freight trains may be released at slow 
speeds with less danger of the train being broken in two. 

Q. What is the distinguishing valve of the ET equip- 
ment? 

A. The distributing valve. 

Q. No auxiliaries being used with the ET brake, where 
is the air taken from that is used in the brake cylinders 
to apply the brakes? 

A. From tlie main reservoirs. 

Q. Is this true both when an automatic, and when an 
independent application of the brakes is made? 

A. Yes; with either kind of application, the air used in 
the brake cylinders is taken from the main reservoirs, the 
pressure first being reduced by a reducing valve. 

Q. How are the locomotive brakes operated independ- 
ently of the train brakes? 

A. By the use of the independent brake valve. 

Q. How are the engine and train brakes operated 
simultaneously? 

A. By the use of the automatic brake valve. 



ET Locomotive Brake Equipmext 209 

Q. Referring to Fig. 71, what is the purpose of the 
main reservoir cut-out cock? 

A. When necessary to remove valves to make repairs 
to any part of the equipment after it is charged, this cock 
may be closed to prevent loss of main reservoir air. 

Q. Why is it that but one brake-pipe feed valve is 
used with this equipment? 

A. Because the feed valve used has an improved regulat- 
ing attachment by means of which it can readily be changed 
from one brake-pipe pressure to another. 

Q. What is this brake-pipe feed valve called? 

A. The B-6 feed valve. 

Q. In what respect does the pump governor used with 
this equipment differ from the older type? 

A. In that it automatically adjusts the excess pressure 
whenever the adjustment of the feed valve is changed from 
one brake-pipe pressure to another. 

Q. By what name is this governor known? 

A, It is designated the SF-4:^ or excess pressure gover- 
nor. (See Fig. 43.) 

Q. What is the purpose of the independent brake 
valve? 

A. It enables the engineer to operate the locomotive 
brakes in the same manner that he does now with the 
straight-air brake^ and it also enables him^ when the auto- 
matic brake is applied^ to regulate the cylinder pressure on 
the locomotive^ or to release entirely the locomotive brakes^ 
without effecting the train brakes. 

Q. When the brakes have been applied by the use of 
the automatic brake valve on the lead engine, can the 
helper engineer release the brakes on his engine? 

A. Yes; by placing the independent brake valve in re- 
lease position. He can also reapply them if desired. 



210 Air-Brake Catechism 

Q. Should the engineer after making an automatic ap- 
plication, entirely release the air from the brake cylin- 
ders by the use of the independent brake valve, could he 
again apply them independently of the automatic brake? 

A. Yes. 

Q. How? 

A. By moving the handle of the independent brake valve 
to application position, admitting the desired pressure, and 
then moving it back to running position. It could be re- 
turned to lap position, but if this were done, the brakes on 
the locomotive would not release when the automatic brake 
valve handle was placed in running position, 

Q. What should the engineer do when his engine is 
second, or a helper, in double-heading? 

A. Close the double-heading cock in the brake-pipe un- 
der the brake valve, and leave both brake valve handles in 
running position. 

Q. Has the engineer the means of knowing how much 
pressure is being put into the locomotive brake cylinders 
at all times? 

A. Yes; the red hand of the smaller duplex air gauge 
in the cab shows brake-cylinder pressure at all times. 

Q. What pressures do the hands of the two duplex 
air gauges indicate? 

A. On the large gauge^ the red hand shows main-reser- 
voir pressure; the black hand shows pressure in chamber D, 
(this is commonl}^ considered as representing brake-pipe pres- 
sure) ; on the small gauge, the red hand shows brake-cylinder 
pressure, and the black hand brake-pipe pressure. 

Q. What is the maximum pressure that can be obtained 
in the brake cylinders with the independent brake valve? 

A. Forty-five pounds. 



ET Locomotive Brake Equipment 211 

Q. How is the independent-brake pressure regulated? 

A. By means of the pressure reducing valve^ Fig. 71. 
Q. Does this pressure reducing valve serve the inde- 
pendent brake only? 

A. No; it also does duty for the train air signal when 
the locomotive is equipped with the signal apparatus. 

Q. What is the purpose of the combined strainer and 
check valve used in the signal pipe? 

A. It prevents dirt and other foreign matter from getting 
to the check valve^ causing it to leak^ and the check valve pre- 
vents a back flow of air from the signal pipe to the inde- 
pendent brake valve While the latter is being used. 

Q. If a pump should break down on the second engine, 
and inasmuch as the air for braking purposes is taken 
from the main reservoirs, could the brakes be operated 
on this engine? 

A. Yes; the engineer could open the cut-out cock in the 
*^^dead-engine'^ by-pass connection, which would allow the 
main reservoirs to charge up from the brake-pipe. 

Q. What special adjustment is necessary in case of a 
dead engine? 

A. Owing to the fact that a dead engine is very light, due 
to the fire having been dumped and the water drained off, 
it is not good practice to use full braking pressure on the 
engine on account of the liability of wheel sliding. To pre- 
vent this, the safety valve on the distributing valve should 
have its adjustment reduced to 25 pounds^ thus limiting 
brake-cylinder pressure to this amount. 

Q. What is 'the dead-engine by-pass connection? 

A. It is a by-pass by means of which the main reser- 
voirs can be charged through a cut-out cock and a combined 
air strainer and check valve, the latter having a choke which 
regulates the flow^ of air from the brake-pipe at a speed such 



212 



Air-Brake Catechism 



tliat the air taken from it would not act to apply the train 
brakes while the main reservoirs are charging. The check 
valve prevents air flowing back to the brake-pipe when a re- 
duction is made to appl}^ the brakes, and the strainer pre- 
vents dirt from lodging in the check valve and causing it to 
leak. The cut-out cock must be closed when this connection 
is not being used. 

BRAKE VALVES FOR ET EQUIPMENT. 

H-6 Automatic Brake Valve. 




Fig. 72.— Type H-6 Brake Valve. 



Q. How many positions has the H-6 automatic brak< 
valve handle? 
A. Six, 



feed valve 
H" pipe tap 




Fig. 73 



ROTARY VALVE SEAT 




TRANSPARENT 

PLAN OF 
ROTARY VALVE. 




18 TO GAUGE 

(black handle) 



PIPE TAP 
EQUALIZING' RESERVOIR 



THE H-6 AUTOMATIC BRAKE VALVE 

RUNNING POSITION 



MAIN ATMOSPHERIC BRAKE PIPE EQUALIZING FEED 
RESERVOIR PRESSURE RESERVOIR VALVE PIPE 

PRESSURE PRESSURE PRESSURE 



Copyri<rht, 1909, by The Norman W, Henley Publishing Co. 



ET Locomotive Brake Equipment 213 

Q. Name them. 

A. They are release, running, hokhng (see Fig. 74), lap, 
service application, and emergency application positions. 

Q. What is the purpose of each? 

A. With the exception of release and locomotive brake 
holding, they are the same as the corresponding positions 
on the G-6 brake valve which have already been described 
in the first part of the book. 

In release position the train brakes can be released but 
not the locomotive brakes, and moving the handle back and 
forth between driver brake holding and running, or between 
release and running i)osition, the locomotive brakes can be 
graduated off after the train brakes are released or while 
they are releasing. Locomotive brake holding position, as 
its name implies, is for the purpose of holding these brakes 
applied until it is desired to release them. In this position 
the feed valve controls brake-pipe pressure. 

Q. What are the advantages of holding position? 

A. When releasing brakes on long freight trains the slack 
may be held bunched, thus preventing a break-in-two, es- 
pecially when release is made at low speed. This may also 
be done by leaving the brake-valve handle in release posi- 
tion; the handle may be moved to holding position to avoid 
overcharging. With passenger trains, sn^oother and more 
accurate stops can be made^ because train brakes may be re- 
leased just before stopping, and locomotive brakes gradua- 
ted off afterward. 

Q. When the handle of the H-6 brake valve is placed 
in emergency position is any additional braking power 
obtained in the locomotive brake cylinders? 

A. Yes ; about 30 per cent. 

Q. Explain this. 

A, When the handle is placed in emergency position, 



214 



Air-Brake Catechism 






i 




w 
o 



> 

< 



^ 
t- 






ET Locomotive Brake Equipment 215 

main-reservoir pressure feeds through the brake-valve into 
the application-cylinder pipe, and thence to the application- 
cylinder of the distributing valve, raising the pressure there- 
in to an amount slightly above the adjustment of the safety 
valve. 

Q. What are the advantages of this increased pres- 
sure? 

A. It helps to make a shorter stop, and effectually pre- 
vents possibility of the engine breaking away from the train 
in emergency applications. 

Q. With what type of equipment is this brake valve 
(Fig. 72) used? 

A. With the ET engine and tender brake equipment. 
Q. Is its principle of operation any different from that 
of the G-6 brake valve, already described? 

A. ^0, it is designed on practically the same lines. 

Q. In what particulars does it differ from the G-6 
brake valve? 

A. First, in that it has a permanent base to which it is 
bolted, rendering it unnecessary to disturb any pipe joints 
whenever it is necessary to remove it for cleaning and repairs ; 
second, in that it has, in addition to the same positions for 
the handle, one more position know^n as the holding in which 
the locomotive brakes are held applied while the train brakes 
are releasing; third, that the service exhaust is made at the 
center of the rotary instead of the side; fourth, that in re- 
lease position the engine and tender brakes are held applied; 
fifth, in emergency application position it feeds main-reser- 
voir pressure into the application-cylinder of the distribu- 
ting valve, thus increasing the pressure in the latter and hence 
in the brake cylinders, about thirty per cent ; sixth, it has a 
feed-valve pipe connection; seventh, a distributing-valve-re- 
lease pipe connection. 



216 



Aie-Beake Catechism 



. recD VALVE 

X PIPE TAP^^' - 




7 

tiAIN R£5CR.va/R. 



Fig. 75.— H-6 Automatic Bkake Valve. 



ET Locomotive Brake Equipment 217 

Q. What is Fig. 72? 

A. It is a view of the exterior of the brake valve. 
Q. What does Fig. 74 represent? 

A. It represents tlie top of the brake valves, and shows 
the different positions of the handles for oj^erating them. 

Q. What do Figs. 73 and 75 show? 

A. Figs. 73 and 75 are views showing all the parts with 
their numbers and names. 

Q. Name the parts. 

A. They are as follows: 2, Bottom Case; 3, Eotary- Valve 
Seat; -i, Top Case; 5^ Pipe Bracket; 6, Eotary Valve; 7^ 
Eotary- Valve Key; 8^ Key Washer; 9, Handle; 10^ Handle- 
Latch Spring; 11^ Handle Latch; 12^ Handle-Latch Screw; 
13^ Handle Nut; 14^ Handle Lock ]^nt; 15^ Equalizing Pis- 
ton; 16^ Equalizing-Piston Packing Eing; 17^ Valve-Seat 
Upper Gasket; 18^ A^alve-Seat Lower Gasket; 19, Pipe-Brac- 
ket Gasket; 20^ Small Union N^ut; 21, Brake- Valve Tee; 
22;, Small Union Swivel; 23^ Large Union Nut; 21:, Large 
Union Swivel; 25, Bracket Stud; 26, Bracket Stud Nut; 27, 
Bolt and Nut; 28, Cap ^crew; 29, Oil Plug; 30, Eotary Valve 
Spring; 31, Service-Exhaust Fitting. 

Q. In Fig. 75 three distinct views are given. Name 
them. 

A. That at the top is a section showing the rotary valve 
seat and the arrangement of the ports in it ; that at the right 
is a drawing of the rotary valve, and shows the arrangement 
of the ports and cavities in it ; the lower cut is a longitudinal 
section through the body of the whole brake valve showing 
the interior construction, the equalizing discharge piston, 
and the service exhaust. In this drawing the pipe connec- 
tions are also shown. 

Q. Explain the pipe connections of the H-6 brake 
valve. 

A. Eeferring to the piping diagram, Fig. 71, they are 



218 Air-Beake Catechism 

as follows : Main-reservoir pipe ; feed- valve pipe ; brake-pipe ; 
independent brake valve and application cylinder; distribu- 
ting-valve release; excess-pressure pump governor; and one 
to the air gauge and equalizing reservoir connections. 

Q. Are these connections made to the brake valve 
proper or to its ba,se or pipe bracket? 

A. They are made to the pipe bracket. 

Q. Explain the operation of the H-6 brake valve. 

A. Release Position: In this position the large port a 
of the rotary is brought into full register with the large 
port h (Figs. 73 and 75) leading to the circular cavity that 
extends around under the rotary seat to port c, which leads 
directly into the brake-pipe^ thus providing a direct passage 
for main-reservoir air into the brake-pipe. In this position 
the port I which leads from the application cylinder through 
the independent brake valve to the rotary seat is closed so 
that the application cylinder air cannot escape^ nor the engine 
and tender brakes release; the warning port r is open to the 
atmosphere^ through the exhaust allowing a small quantity 
of air to escape from the feed-valve pipe, in the rotary valve 
which then connects ports r and d. Ports ; in the rotary 
and port g in the seat, leading to chamber D, are in register 
so that air can flow freely to this chamber and the equalizing 
reservoir connected with it. Port s in the rotary and port 
p in the seat are in communication so that main reservoir 
air can flow to the excess pressure top of the pump governor. 

Running Position: In this i)osition port a in the rotary 
is blanked by the rotary seat and air at feed valve pres- 
sure, then enters the brake valve at port d in the rotary seat, 
leading from the feed valve, passes through cavity / in the 
rotary valve face into port h around through the cavity reach- 
ing to port c and thence to the brake pipe. In this position, 
brake-pipe air goes to chamber D and the equalizing reser- 



ET Locomotive Brake Equipment 219 

voir through port c in the rotary seat^ cavity h in the ro- 
tary^ and port g. 

In this position port I in the seat is in register with port 
and passage li in the rotary^ so that air from the application 
cylinder of the distributing valve can escape to the atmos- 
phere, and release the engine and tender brakes. Main- 
reservoir pressure continues to reach the low-pressure gover- 
nor head through port s in the rotary, port p in the seat, and 
a suitable pipe connection. 

Holding Position: Air from the feed-valve pipe flows to 
the brake-pipe through the same ports as in running position, 
but the port I is blanked so that the air cannot escape from 
the application cylinder and the brakes on the engine and 
tender remain applied, and the feed valve controls brake- 
pipe pressure. The same connection to the governor still 
exists as in running position. 

Lap Position: All ports in the brake valve are lapped. 
The maximum-pressure governor head now controls the pump. 

Service Application Position: Port c, the preliminary 
exhaust port leading from chamber D and the equalizing 
reservoir, is in register with port and passage h in the rotary 
leading into the exhaust EX, thus permitting the pressure 
above the equalizing discharge piston and valve 15 to re- 
duce, and the latter to rise and discharge brake-pipe air to 
the atmosphere. When the brake-pipe pressure below the 
equalizing discharge piston reduces to an amount slightly 
below that remaining in chamber D and the equalizing reser- 
voir, it will close the service exhaust and prevent further re- 
duction in brake-pipe pressure. The operation of the H-6 
brake valve in service applications is precisely the same as 
that of the Gr-6 brake valve already described. 

Emergency Position: The large cavity x in the rotary, 
which leads to the emergency exhaust port EX, and the large 
brake-pipe port c, are in register, so that brake-pipe air has 



220 Air-Brake Catechism 

a free escape to the atmosphere^ thus providing for the quick 
reduction of brake-pipe pressure. At the same time port j 
through the rotary valve registers with the groove in the seat 
connecting with port d; cavity h also registers with this 
groove; the small port n connects cavity h with port u in 
the seat; therefore main-reservoir air flows through port j, 
the groove in the seat^ cavity Jv, ports n and u to the appli- 
cation-cylinder pipe, and thence to the application cylinder 
of the distributing valve. This augments the maximum 
pressure in this chamber about 30 per cent in an emergency 
application of the brake. At the same time, a small port 
connects cavity x in the rotary valve with port g in the seat, 
and as cavity x is always in communication with the exhaust 
port EX, the pressure in chamber D and equalizing reser- 
voir is released to the atmosphere. 

Q. For what purpose is the plug 29? 

A. This is an oil plug that provides a convenient means 
of oiling the rotary valve. Whenever the rotary begins to 
show signs of working hard, this plug may be removed and 
valve oil poured in until it appears at the level of the hole, 
when the plug should be screwed back. It should be borne 
in mind, however, that there should be no air pressure on 
the rotary when this plug is removed. 

Q. Where does the oil go that is thus poured into the 
rotary? 

A. It fills up the small annular space in the body 4, which 
surrounds the rotary and its seat at their line of meeting. 

Q. How does this oil get upon the rotary seat? 

A. When the rotary is under pressure the oil in the an- 
nular space is also under pressure, and as the rotary is 
turned in operating the brake, the oil is worked in between 
the rotary and its seat in a thin film, keeping it nicely lubri- 
cated. 



ET Locomotive Brake Equipment 221 

Q. Aside from the lubricating the rotary and its seat, 
does the oil have any other effect on the workiilg of the 
valve? 

A. Yes^ it tends to keep the rotary from leaking by 
keeping the parts well lubricated and thus avoids cutting. 

Q. When it is desired to remove the brake valve for 
repairs, what is necessary to do? 

A. Unscrew the bolts and nuts and. lift the valve off its 
base. No pipe connections need to be disturbed. 

Q. After removal to take the valve apart, v^hat is 
necessary? 

A. Unscrew the cap screws. 

Q. What is the purpose of the small plug, with the side 
outlet in it, that is screwed in the service exhaust open- 
ing? 

A. This small plug is provided with the side outlet to 
change the direction of the exhaust and prevent the escap- 
ing air from blowing on to the feet of the engineman. 

The S-G Independent Brake Valve. 

Q. What is represented in Pigs. 76, 77 and 78? 

A. The independent brake valve^ Fig. 76 being an ex- 
terior view, Fig. 77 a sectional view, showing the rotary seat 
with its ports and also the arrangement of the interior parts. 
Fig. 78 shows the different positions of the brake valve handle, 
a plan of the rotary valve and an interior view of all its parts. 

Q. What are the names of the parts of the independent 
brake valve as numbered on Fig*. 78? 

A. 2, Pipe Bracket; 3^ Eotary- Valve Seat; 4, Valve 
Body; 5^ Return-Spring Casing; G, Return Spring; 7, Cover; 
8^ Casing Screw; 9^ Rotary Valve;' 10^ Rotary- Valve Key; 



222 



Air-Brake Catechism 



11, Rotary- Valve Spring; 12, Key Washer; 13, Upper 
Clutch; 14, Handle Nut; 15, Handle; 16, Handle-Latch 
Spring; 17, Latch Screw; 18, Handle Latch; 19^ Cover 
Screw; 20, Oil Plug; 21, Bolt and Nut; 22, Bracket Stud; 
23, Stud Nut; 24, Upper Gasket; 25, Lower Gasket; 26, 
Lower Clutch; 27, Return-Spring Stop; 28, Cap Screw. 

Q. How is this valve connected up with respect to pip- 
ing? 

A. As shown in tlie piping diagram. Fig. 71, 
it has one pipe connection to the automatic brake valve, one 




Fig. 76. — The S-6 Independent Brake Valve. 

to the application cylinder of the distributing valve, one to 
the distributing-valve exhaust, and one to the air supply. 

Q. Does it have these pipe connections made direct to 
the brake valve or are they made to a permanent base the 
same as with the automatic brake valve? 

A. The pipes are directly connected to a bracket and it 
is not necessary to disturb pipe joints to remove the oper- 
ative parts of the valve. 

Q. Why is the independent brake valve supplied in ad- 



2,3 II f" PIPE TAP 



n V Xi. S h^lf^t I AK 



IV I" PIPE. TAP 




REDUCING 

VALVE 
PRESSURE 



] [ 



DISTRIBUTING DISTRIBUTING APPLICATION ATMOSPHERIC 

VALVE VALVE CYLINDER 

EXHAUST EXHAUST PRESSURE 

PIPE TO PIPE TO AUTOMATIC 

DISTRIBUTING VALVE DRAKE VALVE 



'~f^ Independent Brake- Valve. Sectional elevation, plan 

\aew ot rotary-valve seat, and transparent plan view of rotary 
valve. 



copyright, 1909, by The Norman W. Henley Publishing Co. 



ET Locomotive Brake Equipment 223 

dition to the automatic brake valve with the ET equip- 
ment? 

A. So that the locomotive brakes^ if desired, may be 
operated independently of the automatic brakes both on the 
engine and on the train at all times. 

Q. Name the different positions for the brake valve 
handle. 

A. They are release, running^ lap, slow application and 
quick application positions. 

Q. Explain the different positions of the Independent 
Brake Valve (Fig. 78). 

A. The position at the left is release; this can be used 
regardless of the position of the automatic brake valve 
handle to obtain an independent release. If the hand is 
removed from the handle when in this position the return 
spring automatically returns it to running position. 

Eunning position is the normal position when the valve is 
not in use. If the automatic brake valve is in running posi- 
tion the brakes on the locomotive can be released by placing 
tlie Independent Brake Valve handle in running position. 
It is necessary for the handle to be in this position for the 
brakes on the locomotive to release when the handle of the 
automatic brake valve is placed in running position. 

Lap position; in this position all ports are closed. 

Slow-application position; the use of this position permits 
air pressure to gradually flow to the application cylinder of 
the distributing valve/ thus causing the brakes to apply on 
tlie locomotive. 

Quick-application position; in this position air pressure 
flows quickly into the application cylinder^ causing a prompt 
application of locomotive brakes. 

Q. When the handle is in release position, how are the 
brakes released? 

A. When the handle is in release position port d. Fig. 78, 



224 



Air-Brake Catechism 



St3 UHp\Pz taf> 








z 



Fig. 78. — Ixtekior Views of the S-6 Independent Brake Valve. 



ET Locomotive Brake Equipment 225 

leading to the application C3dinder of the distributing valve^ 
is open to the atmosphere through exhaust port g in the 
rotary and central exhaust port h in the seat, so that the air 
can escape from the application cylinder^ thus permitting 
the brakes to release. 

Q. When the handle is placed in release position, will 
it remain there if the hand is removed? 

A. No^ it will be returned automatically to running po- 
sition by return spring 6. 

Q. Where should the handle be carried when the in- 
dependent valve is not in use? 

A. Always in running position. 

Q. What is the relation of the ports in running posi- 
tion? 

A. In running position port a and port c in the rotary 
seat are in communication through passage / in the rotary, 
so that air from the distributing- valve exhaust may pass 
through the independent brake valve to the automatic brake 
valve, where it can escape to the atmosphere, when the handle 
of the latter is in running position. 

Q. Why are ports a, c, and passage f so arranged? 

A. To enable the engineer, whenever operating the auto- 
matic brake, to hold the locomotive brake applied when re- 
lasing the automatic brakes; that is, to enable him to con- 
trol the escape of air from the application cylinder when re- 
leasing. 

Q. How are the brakes applied independently? 

A. By moving the handle to either application position 
and admitting air to the application cylinder. 

Q. How are the ports arranged in slow application 
position? 

A. Supply port h and service port d are connected by the 



226 Air-Brake Catechism 

circular cavity e and small port m, and air can flow from the 
supply direct to the application cylinder. 

Q. How are the ports arranged in quick application 
position? 

A. Ports 1) and d both connect with cavity e, giving a 
more rapid flow of air from the supply to the application 
cylinder than in slow application position. 

Q. What is lap position for? 

A. To blank all ports when the brakes have been applied 
independently with the desired degree of force. 

Q. What is the maximum brake-cylinder pressure ob- 
tainable with the independent brake valve? 

A. Forty-five pounds. 
Q. Why is this? 

A. Because the air that comes from the main reservoir 
to the independent brake valve must first pass through a 
pressure-reducing valve, adjusted at 45 pounds; this valve 
is located in the main-reservoir pipe at a point before it 
reaches the independent brake valve. 

Q. Trace the air through the independent brake valve*? 

A. Air from the main reservoir, reduced in pressure to 
45 pounds, enters the brake valve, at the supply connection, 
Fig. 78, passes up through port h in the seat to the circular 
cavity e in the face of the rotary and through the port at 
the right hand end of this cavity to the top of the rotary. 
There is always' independent-brake pressure, 45 pounds, on 
top of the rotary with the handle of the brake valve in any 
of its positions. With the handle in application position, 
port h and port d are connected by the cavity e (and port 
m), and air can flow into application cylinder pipe to the 
application cylinder of tlie disti-ibuting valve to apply the 
brakes. With the handle in lap position communication be- 
tween the various ports is cut off and air cannot flow in 



ET Locomotive Brake Equipment 227 

any direction tlirongh tlie valve. With the handle in run- 
ning position, the passage / in the rotary connects port a 
from the distributing-valve exhaust, and port c, the latter 
leading to the automatic brake valve, so that when the 
handles of both valves are in running position the air may 
escape from the application cylinder to the atmosphere and 
release the brakes. With the handle in release joosition, 
cavity g in the rotary connects port cl with the central ex- 
haust port 7i leading to the atmosphere. 

Q. When is it necessary to use the release position of 
the independent brake valve in order to release the loco- 
motive brakes or reduce the brake-cylinder pressure? 

A. Only when the handle of the automatic brake valve 
is not in running position. 

Q. If it is desired to remove the brake valve for clean- 
ing or repairs, what is it necessary to do? 

A. Unscrew the nuts from bolts 21 and take the valve 
off its base. 

Q. How is the valve taken apart to get at the interior 
parts? 

A. Unscrew the cap screw 28, the cover screws 19, and 
the nut 14, and all parts of the valve may be separated. 

Q. What is the function of the spring 11? 

A. It keeps the key washer 12 and the rotary- valve key 
10 up from the rotary and makes the washer press against 
the valve body 4, thus preventing leakage by the rotary-valve 
key when the pump is first started. It also serves to hold 
tlie rotary on its seat when there is no pressure and thus 
prevents dirt from getting on the valve seat. 

Q. With the independent brake valve, can the locomo- 



228 Air-Brake Catechism 

tive brakes be applied and released under any and all con- 
ditions of service? 

A. Yes, they can be controlled perfectly with the inde- 
pendent brake valve under all conditions of service. 

Q. When the engine is standing alone on ash pits, 
turntables, or sidings, and when doing work about the 
engine, should the independent brake valve be applied and 
left applied? 

A. Yes, this practice should be followed at all such 

times. 

Q. Why is it important to do this? 

A. To avoid possibility of the locomotive moving wher 
not desired, as from a leaky throttle or other cause. 

THE NO. G DISTEIBUTING VALVE. 



Q. What do Pigs. 79 and 80 represent? 

A. They represent the distributing valve and reservoi 
showing its general appearance, pipe connections, and als| 
the double chamber reservoir, with its pressure chamber an 
application chamber. 

Q. Name the pipe connections to the distributing valv< 
and describe them. 

A. Referring to Fig. 79, the connection marked ''M 
is the supply-pipe connection. The supply pipe connec 
tlie main-reservoir pipe and the distributing valve. Tl 
connection marked "i7" is the distributing valve releai 
pipe, and connects the exhaust port through the equalizi: 
slide valve of the distributing valve with the independe: 
brake valve, and when the latter is in running position, e^ 
tends through it to the automatic brake valve. The inti 
mediate connection marked ''If connects the applicati< 



M 




PRESSURES 



] c 



MAIN ATMOSPHERIC PRESSURE TRAIN 

RESESVOIR CHAMBER PIPE 



Fig. 78 a 



. — No. 6 Distributing Valve in Released 



and Charging Position. 



Copyright, 1909, by The Norman W. Henley Publishing Co. 



ET Locomotive Brake Equipment 



229 



cylinder to the independent brake valve, and to the auto- 
matic brake valve. 

Eeferring to Fig. 80, the upper connection is the one that 
connects the distributing valve to the brake cylinders. The 




Fig. 79. — Distributing Valve and 
Double Chambeu Reservoir. 



lower connection is the one between the brake pipe and the 
distributing valve. 

Q. What is the function of the distributing valve? 

A. To admit air to, and to exhaust it from, all the brake 




Fig. 80. — Distributing Valve and Double-Chamber Reservoir. 



230 



Air-Beake Catechism 



cylinders on the locomotive^ both in automatic and in in- 
dependent applications^ and to maintain automatically the 
desired cylinder pressure regardless of cylinder leakage and 
variation in piston travel. 

Q. What are the purposes of the cut-out cocks in the 
brake-cylinder pipe? 



MR 




-43 



::^^^^?^rT"Tl^-^.x^x- ^:-^;■^^ ^ S^^v<^:v- v.^Nl'vT^V -.v.x: Vcx-SKv. ,',v'-^vxo-'; 



Fig. 81. — Release Position — Automatic or Independent. 



ET Locomotive Brake Equipment 



231 



A. In case it is desired to cut out any on6 or all of the 
brakes for any cause^ such as burst hose or broken down 
brake rigging, they may be closed to prevent the brakes from 
applying. 

Q. Should the hose burst either in front of the engine- 
truck brake or of the tender-brake cylinder during a 



MR 







Fig. 82. — Independent Application, 



232 



Air-Beake Catechism 



brake application, would the other brakes release? 

A. No. 

Q. Why is this? 

A. Because of the special choke fittings (Fig. 71) in 
the end of the cut-out cocks toward the brake cylinder, which 
prevent air from passing through them faster than the dis- 
tributing valve can supply it. 



MR 







Fig. 83. — Independent Lap. 



ET Locomotive Brake Equipment 



233 



Q. What is the standard brake-pipe pressure carried 
with the ET brake? 

A. For the ordinary brake 70 pounds; for the high- 
speed brake 110 pounds; and for the double-pressure control 
90 pounds. 

Q. What does Fig. 91 represent? 



MR 




w^^^^^^^^s^^^^^^^^^^^:^^-^-^^^^^ 



Fig. 84. — Automatic Seryice, 



234 



Air-Brake Catechism 



A. It is a sectional drawing showing the interior of the- 
distributing valve as actually constructed. 

Q, Referring to Figs. 80 and 91^ what are the names 
of the parts as numbered? 

A. The proper names of the different parts of the dis- 
tributing valve are as follows : 2, Body ; 3, Application- Valve 
Cover; 4^ Cover Screw; 5^ Application Valve; 6^ Application- 



MR 







-43 



Fig. 85. — Service Lap. 



ET Locomotive Brake Equipment 



23.^ 



Valve Spring; 7, Application-Cylinder Cover; 8, Cylinder- 
Cover Bolt and Nut; 9, Cylinder-Cover Gasket; 10, Appli- 
cation Piston; 11, Piston Follower; 12, Packing Leather 
Expander; 13, Packing Leathe-; 1-1, Application-Piston 
Nut; 15, Application-Piston Packing Ring; 16, Exhaust 
Valve; 17, Exhaust-Valve Spring; 18, Application- Valve 



MR 




%^^<^^^\\^^^^^^^^^^\\^^^\-\-^^"^^ 



Fig 86. — Emergency. 



236 



Air-Brake Catechism 



Pin; 19, Graduating Stem; 20, Application-Piston Gradu- 
ating Spring; 21, Graduating-Stem Nut; 22, Upper Cap 
Nut; 23, Equalizing Cylinder Cap; 21:, Cylinder-Cap Bolt 
and Nut; 25^ Cylinder-Cap Gasket; 26, Equalizing Piston; 
27, Equalizing-Piston Packing Eing; 28, Graduating Valve; 
29, Graduating-Valve Spring; 31, Equalizing-Slide Valve; 
32, Equalizing Slide-Valve Spring; 33^ Lower Cap Nut; 34, 



MR 




^^^^^<:X-^Vc^^^:^v>^^v-^-^^■^^^: xv^;;^.^^^^ 



Fig. 87. — Emergency Lap. 



S^ 



ET Locomotive Brake Equipment 



237 



Safety Valve; 35^ Double Chamber Eeservoir; 36, Eeservoir 
Stud and Nut; 37, Eeservoir Drain Plug; 38, Distributing- 
Valve Drain Cock; 39, Application- Valve Cover Gasket; 40, 
Application-Piston Cotter; 41, Distributing A^alve Gasket 
(not shown); 42, Oil Plug; 43, Safety- Valve Air Strainer; 



MR 




^N^^NN^^NNNNN ^^^^^-^-^^^^^^^^ 



Fig. 88. — Independent Release when Brake has been Applied 

Automatically. 



238 



Air-Brake Catechism 



44, Graduating Sleeve; 45, Cylinder-Cap Nut; 46, Equaliz- 
ing-Piston Graduating Spring. 

Q. What do Figs. 81 to 89 inclusive represent? 

A. They are diagrammatic drawings that represent the 
distributing valve in all of its different operative positions. 

Q. Name these positions. 

A. They are, Fig. 81, Eelease, Automatic or Independent; 



■luis^mh^ 



MR 







Fig. 89. — Emergency, when the Quick-Actiox Cap is Used. 



ET Locomotive Brake Equipment 



239 




PLAN OF 
GRADUATING VALVB 



c 


M^rJ 


-1-^ 


) ( " 


=^n 




=^0 c 


k 


ID 



FACE OF SLIDE VALVE 



) CJC 

V 


r,7 -] 


Z) 





PLAN OF SLIDE VALVE 



^?^ 









'^0 



0^ 

0' 




PLAN OF SLIDE VALVE SEAT 
Pig. 90. — Graduating Valve, Equalizing Slide Valve and Slide 

Valve Seat. 



240 Air-Brake Catechism 

Fig. 82, Independent Application; Fig. 83, Independent 
Lap; Fig. 84, Automatic Service; Fig. 85, Service Lap; 
Fig. 86, Eonergency; Fig. 87^ Emergency Lap; Fig. 88, 
Eelease Position, when locomotive brake is released by in- 
dependent brake-valve after an application by brake-pipe re- 
duction ; Fig. 89, Emergency Position, when the quick- 
action cap is used. 

Q. What is represented in Fig. 90? 

A. Fig. 90 represents the plan of the graduating valve, 
shows two views of the slide valve, face and plan, and a 
plan of the slide valve seat. 

These views show the arrangement of ports as they act- 
ually are constructed, and are not diagrammatic drawings. 

Q. How does the distributing valve charge up the pres- 
sure chamber of the double chamber reservoir? 

A. In precisely the same manner that a triple valve 
charges an auxiliary reservoir; that is, by referring to Fig. 
81, brake pipe air enters the distributing valve at BP, fills 
chamber p^ and flows through the feed groove v at the top 
of piston 26 to the slide valve side of this piston, and thence 
to the pressure chamber through port o until the pressure in 
this chamber is equal to that in chamber p and the brake 
pipe. 

Q. Then the pressure in the pressure chamber, when 
fully charged, is equal on both sides of piston 26? 

A. Yes. 

INDEPENDEN^T APPLICATION. 

Q. What takes place in the distributing valve when 
the handle of the independent brake valve is placed in 
service position? 

A. As shown in Fig. 82, air is admitted directly from 



ET Locomotive Brake Equipment 241 

tins valve to the application cylinder^ forming a pressure 
therein which causes the application piston 10 to move for- 
ward compressing spring 20, until stopped by the graduating 
stem 19. This in turn moves the brake cylinder exhaust 
valve 16, and the application valve 5, over until the former 
closes the brake cylinder exhaust port and the latter opens 
its port. Under these conditions main-reservoir air from 
chamber a is free to flow to the brake cylinders through 
chamber h and port c. 

Q. After the pressure in the brake cylinders becomes 
slightly greater than that in the application chamber what 
takes place? 

A. The application piston 10 and the supply valve are 
moved by the excess pressure and the spring 20 to the inde- 
pendent lap position^ as shown in Fig. 83. The movement 
of the piston is stopped by its striking the exhaust valve 16, 
which does not move. 

Q. How is this valve made to assume this position? 

A. When the pressure in chamber b is slightly greater 
than that in the application cylinder^ piston 10 and appli- 
cation valve 5 move back until valve 5 laps its port, where 
further flow of main-reservoir air to the brake c}dinder is cut 
off, and the brake remains applied with a pressure equal to or 
slightly in excess of that in the application cylinder. 

Q. Suppose that after application valve 5 moves to lap 
position, leakage of air from the brake cylinders should 
cause the pressure therein to fall, what would occur? 

A. As soon as the pressure in chamber h fell slightly 
below that in the application cylinder, the application piston 
10 would be forced to the right and application valve 5 would 
open its port and admit main-reservoir air again to supply 
the leakage and raise the brake-cylinder pressure practically 



242 



Air-Bkake Catechism 



equal to that in the application chamber and the application 
cylinder, then move back to lap. 

Q. How are the brakes released after an independent 
application? 




CYLS. 



Fig. 91. — Distributing Valve Showing Connections. 

A. By placing the handle of the independent brake valve 
in running position, when the air in tlie application cylinder 
will escape to the atmosphere ; the pressure in chamber h will 
then force the application piston and both valves to release 



ET Locomotive Brake Equipment 243 

position, as shown in Fig. 81, and brake-cylinder air will 
then escape to the atmosphere through the exhaust ports in 
exhaust valve 16, and in the bodj^ of the distributing valve. 

Q. What position must the handle of the automatic 
brake valve be in that the air may escape from the ap- 
plication cylinder when the handle of the independent 
brake valve is in running position? 

A. In running position. 

Q. Does the equalizing piston 26 and its attached parts 
operate during an independent application and release? 

A. No; they remain inoperative, as shown in Figs. 81, 

82 and 83. 

AUTOMATIC OPERATION". 

Q. How is an automatic service application of the 
brake made? 

A. By moving the handle of the automatic brake valve 
to service position and making the desired brake pipe 
reduction. 

Q. When a reduction in brake-pipe pressure takes 
place, what happens in the distributing valve? 

A. With the pressure chamber charged equal to that in 
the brake pipe^ a reduction in brake pipe pressure causes 
equalizing piston 26 to move to the right (Fig. 84)^ carry- 
ing with it slide valve 31 until the knob on the piston strikes 
the graduating sleeve 44^ which closes the exhaust port lead- 
ing from the application chamber to the distributing-valve 
release pipe, and the graduating valve 28 is moved to the 
right until it uncovers the service port z, which leads into 
passage li and the application cylinder, and through cavity 
n and port w to the application chamber, thus allowing air 
from the pressure chamber to flow into the application 



244 Air-Brake Catechism 

cylinder and chamber. The pressure thus formed in the appli- 
cation cylinder and chamber causes the application piston 10, 
exhaust valve 16, and application valve 5 to assume the posi- 
tion shown in Fig. 84, "Automatic Service," and apply the 

brakes. 

When the pressure in the pressure chamber falls slightly 
below that in the brake pipe, equalizing piston 26 moves 
back, carrying with it the graduating valve 28, without 
moving slide valve 31, until the graduating valve closes port 
%, and prevents any further flow of air from the pressure 
chamber to the application chamber. It is then in ''Service 
Lap'' position as shown in Fig. 85. 

Q. How much of a brake-pipe service reduction is re- 
quired to set the brake in full? 

A. About 20 pounds, the same as with a triple valve. 

Q. How is the brake released by the automatic brake 
valve? 

A. An increase of brake pipe pressure raises that in 
chamber ^ (Fig. 85) of the distributing valve. This pres- 
sure being greater than that in the pressure chamber of the 
distributing valve, forces piston 26, and the parts controlled 
by this piston, to the left. In this position the pressure from 
the application cylinder and the application chamber is free 
to flow through port li and the independent brake valve to 
the automatic brake valve, from whence it may escape to the 
atmosphere when the brake valve handle is in running posi- 
tion. 

The escape of the pressure through port /^, connected with 
the applicaton cylinder, reduces the pressure in this cylinder 
and permits the greater pressure in chamber h to force piston 
10 to the left; it in turn draws the parts attached to it to 
a corresponding position (Fig. 81). In this position brake- 
cylinder pressure escapes to the atmosphere through ports 



ET Locomotive Brake Equipment 245 

d and e in the seat of the slide valve 16 and the brakes on 
the locomotive release. <^ 

Q. How is an automatic emergency application made? 

A. By making a quick^ heavy brake-pipe reduction^ when 
the equalizing piston 26^ with equalizing slide valve 31^ and 
graduating valve 28^ will move their full stroke with suf- 
ficient force to compress the graduating spring 46, strike 
against the gasket 35, and open port li wide to the applica- 
tion cylinder without opening port w to the application 
chamber, as shown in Fig. 86, permitting full equalization 
between the pressure chamber and the application cylinder 
only, which, being very small in volume compared to the pres- 
sure chamber, will equalize at a much higher pressure than 
when the application chamber is connected to the application 
cylinder ; thus applying the brakes with a much greater force 
than in a full service application. 

Q. Are there any other times when the application 
chamber and application cylinder are not connected? 

A. No; only in emergency applications. 

Q. From what other source is air pressure supplied to 
the distributing valve in emergency applications? 

A. When the handle of the automatic brake valve is in 
emergency position, main-reservoir air feeds through ports 
in the rotary valve and seat to the application-cylinder pipe, 
and thence directly into the application cylinder of the dis- 
tributing valve through port Ji. 

Q. How much pressure is obtained in the application 
cylinder and the brake cylinders in an emergency applica- 
tion? 

A. Assuming the brake-pipe pressure to be 70 pounds, 
about 65 pounds is had in the brake cylinders. 

Q. How is this additional 15 pounds obtained? 

A. By the higher equalization of application cylinder 
and pressure chamber^ and the maintaining of the resulting 



246 Air-Beake Catechism 

pressure by the flow of main-reservoir air through the brake 
valve and application-cylinder pipe. 

Q. What provision is made to prevent too high a pres- 
sure in the brake cylinder? 

A. The safety valve, as shown in Fig. 86, is connected 
through ports in the equalizing slide valve to the application 
cylinder, and when the pressure becomes higher than its limit 
of adjustment {6S pounds) it opens and vents the surplus 
air to the atmosphere. 

Q. What is the emergency lap position of the distribut- 
ing valve? 

A. It is the position shown in Fig. 87, in which the 
application piston 10 and application valve 5 have been 
moved back by excess pressure and graduating spring 20 
far enough to close the port in the supply valve and prevent 
further flow of main-reservoir air to the brake cylinders. 

Q. What does Fig. 88 illustrate? 

A. It illustrates the positions of the various valves in 
the distributing valve after an automatic application, and 
then an independent release have been made. 

Q. In what kind of application do the equalizing piston 
26 and the slide valve 28 and 31 operate? 

A. In all automatic applications of the brake both serv- 
ice and emergency. 

Q. How much pressure can be had in the brake cylin- 
der in a full service application? In an emergency? 

A. When the brake-j^ipe pressure is TO pounds, about 50 
pounds, the same as with the present brake in a service ap- 
plication. In an emergency application the cylinder pres- 
sure would approximate 65 pounds. 

Q. Suppose the high-speed-brake pressure of 110 
pounds is being used, how much will be had in the ap- 
plication cylinder in an emergency application? 



ET Locomotive Brake Equipment 2J:7 

A. About 90 pounds; the same will be had in the brake 
cylinders, and these pressures will gradually be reduced to 
68 pounds by the safety valve. 

Q. Is it necessary to break any pipe joints when re- 
moving the distributing valve from the double-chamber 
reservoir? 

A. No; all the pipe connections are made to the double- 
chamber reservoir proper. 

Q. Suppose it V7ere desired to remove the application 
piston, how should this be done? 

A. The application-valve cover 3 should first be removed, 
then the application ' valve 5 and the application-valve pin 
18 should be taken out. after which the application-cylinder 
cover can be removed and the application piston taken out 
for inspection and repairs. 

Q. What is the purpose of the small port u? 

A. It forms a passage for any water that may deposit in 
the cylinder to the right of the application piston to drain 
off into port m, where it runs to the bottom of the valve, 
and should be drawn off each trip by means of the drain 
cock 38. 

The Quick-Action Cylinder Cap. 

Q. What device is illustrated in Fig. 92? 

A. The quick-action cylinder cap. 

Q. With w^hat valve is this used? 

A. The distributing valve. 

Q. What is the purpose of this cap? 

A. It furnishes a means of obtaining quick-action with 
the distributing valve the same as is obtained with a quick- 
action triple valve; that is^ it vents a portion of the brake- 



248 



Air-Brake Catechism 



pipe pressure into the locomotive brake cylinders in emer- 
genc}^ applications. 

Q. What effect has this on the train? 

A. It quickens the reduction of brake-pipe pressure, 
making it more certain that all quick-action triple valves in 
the train will go to emergency position. 



^^"^^ 




Fig. 92. — Quick-Action Cylinder Cap. 



Q. When is this cap used? 

A. In the same class of service that uses quick-action 
triple valves on the tender with the old standard locomotive 
brake. 

Q. It is not then a standard part of the ET equip- 
ment? 

A. Xo; only when conditions require it. 



ET Locomotive Brake Equipment 249 

Q. When used, how is it attached to the distributing 
valve? 

A. The plain cylinder cap 23 is removed, and the quick- 
action cap put in its place. 

Q. Referring to Fig. 92, what are the parts of the 
quick-action cylinder cap? 

A. 44^ Cylinder-Cap Body; 45^ Stop Nut; 46^ Graduat- 
ing Spring; 47^ Bushing; 48, Slide Valve; 49, Check-Valve 
IS^ut; 50, Check- Valve Seat; 51, Check- Valve Nut; 52, 
Check- Valve Rubber Seat; 53, Check Valve; 54, Check- 
Valve Spring; 55, Graduating- Spring Nut; 56, Slide- Valve 
Pin; 57, Slide- Valve 'Spring ; 58, Graduating-Stem Pin; 59, 
Graduating Stem. 

Q. Referring to Fig. 89, how does this cap operate? 

A. In an emergency application, equalizing piston 26 
moves rapidly to the right, its knob striking graduating 
stem 59 and compressing the graduating spring, until it 
strikes the cylinder-cap gasket. The movement of the gradu- 
ating stem carries with it slide valve 48, and opens port j, 
allowing brake-pipe air to flow to cavity x, force down check 
valve 53 and flow through ports m and c to the brake cylin- 
ders on the locomotive. The other parts of the distributing 
valve operate exactly as already described for emergency ap- 
plications. As soon as the decreasing pressure in the brake 
pipe becomes equal with the increasing pressure in the brake- 
cylinder pipe, check valve 53 is forced to its seat by spring 
54, and prevents any air flowing from the brake cylinders 
back into the brake pipe. When the brakes are released 
after an emergency application, piston 26 is forced to the 
release position, as already described, and the graduating 
spring forces graduating stem 59 and slide valve 48 to the 
position shown in Fig. 89, closing port j, and preventing 
brake-pipe air from flo\viiig to the brake cylinders. 



250 Air-Brake Catechism 

Q. How does it operate when automatic service ap- 
plications are made? 

A. The parts do not move; the graduating stem 59 forms 
the stop against which the equalizing piston strikes^ exactly 
the same as graduating sleeve 4,4: in the plain cylinder cap. 

Q. What would occur if slide valve 48 leaked? 

A. There would be a slight blow at the brake-cylinder 
exliaust of the distributing valve in release. 

The Use of the Safety Valve. 

Q. What function does the safety valve, shown in 
Figs. 79 and 80, perform when attached to the distribut- 
ing valve? 

A. It performs all the functions of the ordinary brake 
cylinder relief valve and in addition those of the high-speed 
reducing valves. 

Q. What are the names of the different parts of this 
device? 

A. As shown in the illustration they are, 2, Body; 3. 
Cap Nut; -i, Valve; 5, Valve Stem; 6, Adjusting Spring; 
7, Adjusting Nut. 

Q. Of what peculiar style or variety is this valve? 

A. It is known as the pop-valve style. 

Q. At what pressure is this valve usually adjusted 
when used in the ET equipment? 

A. At 68 pounds. 

Q. Explain its operation. 

A. The adjustment of the valve is effected by screw- 
ing down the regulating nut 7 until the adjusting spring 
has sufficient tension to hold valve 4, against the pressure 
it is desired to retain^ after which the cap nut 3 is screwed 
on firmly in place. When the air pressure acting upward 



ET Locomotive Brake Equipment 251 

on valve \ is greater than the adjusting spring can re- 
sist^ this valve will lift from its seat^ exposing a slightly 
greater area to the pressure below, which causes it to move 
promptly the whole length of its travel^ or until the stem 
strikes the cap nut^ and allow the surplus air to escape through 
the two bottom ports in the body 2. 

Q. What is the object of the by-pass port that leads 
up into the chamber in the body 2 above valve 4? 

A. When valve -i lifts to relieve pressure it travels far 
enough to cover the upper end of the by-pass port, thus pre- 
venting air in any considerable quantity from passing into 
the chamber above. .When it commences to lower^ it grad- 
ually opens this port^ and closes the lower ports to the atmos- 
phere, allowing air to pass into the upper chamber,, where 
it will then form a pressure above valve 4 and cause it to 
seat promptly. There are two relief ports in the chamber to 
allow the air remaining therein to escape after valve 4 closes ; 
while valve 4 uncovers the upper end of this by-pass port 
the two relief ports can not allow the air to escape so fast 
but that pressure will be formed in the upper chamber in 
the valve body. 

FEED VALVES. 
the b-6 feed valve. 

Q. What is Fig. 93? 

A. It is a photographic view of the exterior of the feed 
valve, used with the ET equipment, to regulate the pressure 
in the brake-pipe when the handle of the automatic brake 
valve is in running or in holding position. 

Q. How does this feed valve differ from the slide valve 
feed valve used with the G-6 brake valve? 

A. Its operation is the same except that^ by the use of 



252 



Air-Bkake Catechism 



the adjusting wheel it can be adjusted for the pressure desired. 
It is also different in detail, having a larger regulating valve 
a supply valve with a port in it, and a different supply valve 
piston. For description of its operation see G-6 Feed A^alve. 

Q. What advantage does this adjusting feature give 
over that of the older feed valve? 

A. It makes it possible to dispense with one of the two 




Fig. 93.— B-6 Feed Valve. 



feed valves now used with the high-speed and the double- 
pressure control brakes, also the ^;eversing cock bracket. 

Q. How is the adjustmenc of the B-6 feed valve 
effected? 

A. By turning the adjusting handle in one direction until 
the pin on it strikes the lower stop the valve will maintain 70 
pounds brake-pipe pressure and by turning it in the other di- 
rection until the pin strikes the upper stop, it will maintain 
110 pounds brake pipe pressure. 






ET Locomotive Brake Equipment 253 

Q. If any other pressures than the above are desired, 
what must be done? 

A. The positions of the stops must be changed. 

THE C-6 REDUCi:NrG VALVE. 

Q. What kind of a reducing valve is used with the 
ET equipment? 

A. It is known as the C-6 and is practically the same as 
the B-6^ except that it does not have the adjusting wheel of 
the former. For a description of its operation see G-6 Feed 
Valve. 

Q. At what pressure is it adjusted? 

A. At 45 pounds. 

Q. To what does this pressure reducing* valve supply 
air? 

A. It supplies both the independent brake and the train 
air signal. 

THE PUMP GOVEENOE. 

Q. What pump governor must be used with the ET 
equipment? 

A. The SF-4 pump governor. 

Q. To what is the upper part of the excess-pressure 
head connected? 

A. The feed-valve pipe. 

Q. What pressure is always in the excess-pressure 
head and the feed-valve pipe connection? 

A. Maximum brake-pipe pressure. 

Q. To what pressure is the maximum-pressure head 
connected? 

A. To the main-reservoir pressure direct. 



254 Aik-Brake Catechism 

Q. Explain the operation of the governor in this equip- 
ment. 

A. The comiection marked A B Y, Fig. -io^ has main-reser- 
voir air flowing through it into the excess-pressure top under 
the air diaphragm 28^ when the handle of the automatic brake 
valve is in release^ running, or holding position; and the 
connection marked FTP has air at maximum brake-pipe 
pressure flowing through it to the spring case above the air 
diaphragm regardless of the position of the brake-valve han- 
dle. Assuming that the tension on the excess-pressure spring 
27 is such that it requires an excess pressure of 20 pounds 
beneath the diaphragm to raise it against the air pressure 
bearing down upon it from above^ the main-reservoir pres- 
sure must be 23 pounds in excess of that in the feed- valve 
pipe before the diaphragm can be lifted and the pump 
stopped. 

If the handle of the automatic brake valve is moved to 
service-application position^ the communication between the 
main reservoir and chamber d of excess pressure top is cut 
off so that the pressure above the diaphragm will hold it down 
with the pin valve on its seat ; this head cannot then control 
the pump. The pump will now work until the main-reservoir 
pressure reaches tliat for which the maximum-pressure head 
at the right is adjusted, say 130 pounds^ when this head will 
operate in the usual manner and stop the pump. 

Wlien the handle is moved to release^ running or holding 
position, main-reservoir air may again flow to the excess-pres- 
sure head to chamber d under the diaphragm. When the 
brake-pipe pressure is restored to the maximum for which 
the feed valve is adjusted, and the handle of the brake valve 
is either in running or in holding position, the pump can 
work until the main reservoir has accumulated the proper 
excess, when the excess-pressure head will operate and stop 
the pump. 



ET Locomotive Brake Equipment 255 

Q. In the piping diaphragm, Fig. 71, there is shown, 
placed in the main-reservoir pipe, a cut-out cock. At what 
point with relation to this cock is the maximum-pressure 
head connected to the main reservoir? 

A. It is connected between this cut-out cock and the 
main reservoir. 

Q. Why is it so located? 

A. So that in case it is necessary to close the cut-out cock 
to make repairs to any other part of the equipment, the 
maximum pressure top can still control the pump^ and pre- 
vent it from pumping up an excessively high main-reservoir 
pressure. 

Q. What happens when this cut-out cock is closed? 

A. A port is so arranged that the air in the main-res- 
ervoir pipe and brake-pipe is vented to the atmosphere^ re- 
sulting in an application of the brake. If the engineer fails 
to open the cock the brakes will not release and the train 
cannot be started. 

DEFECTS OF "ET^^ EQUIPMENT. 

Q. If the application cylinder pipe should leak at any 
of its connections between the distributing valve and the 
independent brake valve, what would be the effect? 

A. It would cause the brakes to leak off both in automatic 
service and in independent brake applications. 

Q. If the pipe connection between the independent and 
the automatic brake valves should leak, what would be 
the effect? 

A. The brake would leak off when the automatic brake- 
valve handle was in holding position, but not at other times. 

Q. Suppose the distributing-valve release pipe should 
leak at any of its connections between the distributing 



256 Air-Brake Catechism 

valve and the independent brake valve, what would be 
the effect? 

A. When an independent brake application was made and 
the handle of the independent brake valve was lapped^ tliis 
leak would permit the brakes to gradually release; in the 
automatic application it would make no difference, but when 
a release of an automatic application of the train brake was 
made it would gradually destroy the holding feature of the 
automatic brake valve. 

Q. If there should be a leak through the rotary of the 
independent brake valve, what would be the eflfect? 

A. While both brakes are released and both brake valves 
are in running position, it will cause a slight blow at the 
emergency exhaust port of the automatic brake valve. When 
either the automatic or the independent brake is applied in 
partial service, it will cause a building up of pressure in the 
application cylinder to the maximum adjustment of the pres- 
sure reducing valve, and hence cause the brakes to apply with 
full independent pressure. It will also cause a building up 
of pressure in the application cylinder, while the handle of 
the automatic brake valve is in release or in holding positions. 

Q. If the main-reservoir connection to the distributing 
valve should leak, what would be the effect? 

A. It would make no difference with the operation of the 
distributing valve, but it would make the pump work harder 
to supply the leak. 

Q. If the application valve 5 should leak, what would 
be the effect, and how could the leak be detected? 

A. It would increase brake-cylinder pressure above that 
in the application cylinder, and force the application piston 
and application valve back far enough to allow the surplus 
air to escape at the brake-cylinder exhaust port. The leaky 



ET Locomotive Brake Equipment 257 

valve would be detected by the escape of brake-cylinder air 
at the exhaust port during a brake application. 

Q. Would this be true if there were leakage in the 
brake cylinders at the same time? 

A. That would depend on whether the leakage from the 
brake cylinders was greater or less than that through the 
application valve. If greater^ there would be no escape of air 
at the brake-cylinder exhaust port; if less^ there would be. 

Q. If the application-piston graduating spring 20 (Fig. 
81) should break, what would be the effect? 

A. The application piston and valvo would be less sensi- 
tive in graduating. 

Q. If the exhaust valve 16 should leak how could it be 
known? 

A. By a blow from the brake-cylinder exhaust port while 
the brakes are applied. 

Q. How would a leaky packing leather and packing 
ring in the application piston affect the operation of the 
distributing valve in brake applications? 

A. It would tend to reduce the efficiency of the valve 
in maintaining any cylinder leakage. 

Q. If equalizing slide valve 31 should leak, what efifect 
would it produce? 

A. When brakes are released and both brake valves are in 
running position^ there would be a slight blow at the emer- 
gency exhaust port of the automatic brake valve. If the in- 
dependent brake were applied there would be an increase in 
application-chamber pressure which would cause the brakes 
to go on harder. If the automatic brake is applied in partial 
service, then application-cylinder pressure would increase and 
the brakes go on harder to the limit of full equalization, if 
ordinary pressure is used; or if high-speed pressure is used. 



258 Air-Brake Catechism 

until the safety valve would open and relieve the application- 
cylinder. 

Q. Suppose the engine having the leaky equalizing 
slide valve were second in a double-header, what might 
happen then? 

A. The brakes might entirely release^ if the application 
were a partial service. 

Q. Suppose the graduating valve 28 should leak, what 
would be the effect? 

A. In release position no effect would be observed. In 
partial service application, the effect would be practically the 
same as stated would occur with a leaky slide valve 31. 

PRINCIPAL DIFFEEENCES BETWEEN THE No. 5 
AND No. 6 ET EQUIPMENTS. 

Piping. In the No. 5 Equipment, the double-heading cock 
is a double cut-out cochj one passage for the brake-pipe, and 
the other for the douhle-lieading pipe, the latter taking the 
place of the distributing-valve release pipe in the No. 6 equip- 
ment. The double-heading pipe does not connect with the 
Independent Brake Valve. The plug in the double cut-out 
cock is arranged so that when the brake-pipe passage is open, 
the double-heading-pipe passage is closed, and vice versa. 
Consequently the double-heading pipe is only used when the 
engine is second in double heading, or a helper. 

The dead-engine by-pass connection was not furnished witli 
the No. 5 equipment unless specially ordered, so that in many 
cases it will not be found in that equipment. 

A single-pointer air gage was furnished with the No. 5 
equipment in place of the No. 2 duplex gage, its connection 
being to the brake-cylinder pipe only. 

Manipulation. The only difference in manipulation be- 
tween the two equipments is in double heading; with the 



ET Locomotive Brake Equipment 259 

^0. 5 equipment, the double cut-out cock is turned to close 
he brake-pipe^ and the handle of the automatic brake valve 
)laced on lap on all engines except the one from which the 
)rakes are being operated. In all cases of application and 
elease of the brakes^ the manipulation is exactly the same. 

Auiomatic Brake Valve. The H-5 automatic brake-valve 
ised with the No. 5 equipment differs from the H-G Valve 
n the arrangement of ports in rotary valve and seat; in an 
emergency application, the equilizing reservoir is connected 
v^ith the application chamber of the distributing valve, there- 
)y increasing the volume of the latter and it's pressure of 
qualization with the pressure chamber to obtain the in- 
creased emergency brake-cylinder pressure; but the increase 
)btained by this arrangement is only about 20 per cent, in- 
tead of 30 per cent, as obtained with the No. 6 equipment. 

In the II-5 brake-valve, main-reservoir pressure does not 
eed into the application cylinder of the distributing valve; 
n the No. 5 equipment, this feeding occurs in the distribu- 
ing valve itself. 

In the II-5 brake-valve, the warning port blows main-reser- 
i^oir air to the atmosphere instead of feed-valvc-pipe air. Also 
when the handle is on lap, the double-heading pipe connection 
s connected to the atmosphere. 

Independent Brake Valve. The SF Independent Brake 

Valve, used with the No. 5 equipment, has only three pipe 

onnections, and is quite different in arrangement of ports 

md details from the S-6 valve just described. Its manipula- 

ion, however, is just the same. 

Distributing Valve. The No. 5 distributing valve differs 
rom the No. 6 in many ways. The application cylinder and 
ipplication chamber are always directly connected, without 
egard to the position of the equalizing slide valve; a port 
onnects main-reservoir pressure with the equalizing slide- 
^alve seat, which, in emergency applications, feeds main-res- 



260 



Air-Brake Catechism 



ervoir air into the application chamber; the safety valve is 
set for 53 pounds^ instead of 68; port m, (Fig. 86) does 
not exists there being no provision in the No. 5 distributing 
valve for the application of the qnick-action cylinder cap; 
connections II and IV^ (Fig. 86) are reversed in the No. 
5 distributing valve; the main-reservoir and brake-pipe con-| 
nections are for smaller sized pipe ; the arrangement of ports 
in equalizing slide valve and seat are different; the supply | 
valve is of slightly different construction ; there is no gradua- 
ting sleeve and spring in the equalizing piston; there is no | 
drain cock (No. 38^ Fig. 86) , a small pipe plug being used in- 
stead; the arrangement of ports in the end of the double-l 
chamber reservoir are different^ so that a No. 6 distributing! 
valve cannot be used on a No. 5 reservoir^ and vice- versa. 
But it responds to brake-pipe reductions in quite the same 
manner^ so that, outside of the higher emergency brake-cylin- 
der pressure with the later equipment^ an engineer could not| 
tell from the cab which distributing valve was installed. 

All other parts of the two equipments are practically the 
same. 



CHAPTER VIII. 
AIK-SIGNAL SYSTEM. . 

The signal equipment described in this chapter refers to the 
engine equipment used with the old-style Westinghouse ap- 
paratus. 

The arrangement on the cars has not been changed^ while 
that in the new schedule ET Westinghouse equipment has 
been modified slightly. This modification is explained more 
in detail in the chapter covering the ET equipment. 

Q. What form of signal was used before the com- 
pressed-air signaling apparatus was invented? 

A. The old bell rope and gong signal^ such as is now used 
on freight trains. 

Q. Do all roads use the air signal jn passenger service? 

A. Not all^ but most roads do. 

Q. What parts of the signaling apparatus are found on 
the engine? . 

A. The strainer^ the reducing valve (Fig. 99), the whis- 
tle valve (Fig. 98), the whistle (Fig. 100), and the pipe 
connections as shown in Fig. 94. 

Q. What parts are found on the car? 

A. The discharge valve (Fig. 97), the signal cord run- 
ning the length of the car, and the signal-pipe connections 
as shown in Fig. 95. 

Q. Where is the discharge valve (Fig. 97) usually 
located? 

A. As shown in Fig. 95, although it is sometimes found 
inside the car over the door. 



363 



Air-Brake Catechism 



Q. Why is it better placed outside? 

A. When it is so placed the noise of the discharge will 
not affect nervous people. 

Q. How does the car discharge valve work? 

A. The signal cord is attached to the valve in the hole 
of 5 (Fig. 97) ; when the cord is pulled,, valve 3 is forced 
from its seat^ allowing signal-pipe pressure to escape to the 
atmosphere. 




THE ABOVE DIAGRAM IS SIMPLY ILLUSTRATIVE OF THE METHOD 
OF ARRANQINCi THE COMPRESSED AIR TRAIN SICiNALIMQ APPLIANCES, 
AND MAY BE MOUIFItO AS THE CONSTRUCTION OF THE ENGINE DEMANDS. 



Fig. 94. — Signal, Equipment for Engine Not Equipped with 

Schedule E. T. 



Q. What is the trouble when there is a constant leak 
from the discharge valve? 

A. There is dirt on the seat of valve 3 (Fig. 97). 

Q. Where is the signal valve (Fig. 98) located? 

A. In the cab^ where it will not be subjected to severe 
heat or cold. 

Q, Where are the reducing valves (Fig. 99) usually 
placed? 



Air Signal System 



263 



A. It was formerly customary to locate them outside, next 
to the main reservoir, but now good practice locates them 

inside the cab where they cannot freeze in winter. 

Q. What is the duty of these valves? 

A. To maintain a constant pressure in the whistle line. 

Q. Explain the action of the reducing valve (Fig. 99). 

A. Spring 13 controls the movement of piston 10 which, 




Fig. 95. — Location or Signal Apparatus on Coach. 



in turn, forces check-valve 4 from its seat when the tension 
of the spring 10 is more powerful than the pressure down- 
ward on the piston. 

The tension of this spring is usually adjusted to with- 
stand a pressure of 40 pounds acting downward on the piston, 
hence when the pressure is less than this amount the spring 
will raise the piston upward to the position shown in Fig. 
99. In this position air entering from the main reservoir 



264: 



Air-Beake Catechism 



connection at A will pass through the restricted opening 
shown, past the unseated check valve -4 and on, as indicated 
by the arrows, and out to the signal pipe at B. As soon 
as the pressure in chamber C and the signal pipe is greater 
than the tension of spring 13, the piston will be forced down- 
ward, allowing the main-reservoir pressure and the spring 6 
to force the check to its seat. This valve will not open again 
until by leakage or otherwise the pressure in the signal pipe 
has been reduced below 40 pounds. 

Q. Of what use is the plug valve in the upper left-hand 
corner? 

A. To cut out main-reservoir pressure in case we wish to 
take the reducer apart. 




Fig. 96. — Air Strains ek ox Engine. 



Q. What is the object of the air strainer (Fig. 96). 

A. To keep any foreign matter from entering the re- 
ducing valve or signal system, where it may occasion an im- 
proper response of the signals. 

Q. Of what does this strainer consist? 

A. Of the body 8 (Fig. 96), perforated brass discs 3, and 
the space between these perforated plates is filled with curled 
hair. 

Q. Has this strainer ever been used to fulfill an oflSce 
other than as described above? 



Air Signal System 



265 



A. Yes; a tee is sometimes inserted between the strainer 
and the reducing valve. A branch of the tee is then piped 
to the pump governor^ and the strainer performs the double 
duty of keeping foreign matter both from the signal system 
and the pump governor. 

Q. Is any material other than curled hair ever used to 
fill in the space between the perforated plates 3 (Fig. 96)? 

A. Yes; sponge has been used for this purpose^ but the 
results obtained were not satisfactory. The hair seems to 




Fig. 97. — Car Discharge Valve. 



collect the dirt better and it is much easier to clean than 
the sponge^ as it permits of a freer separation. 

Q. Where is the whistle (Fig. 100) located? 

A. In the cab, as near the engineer as convenient. 
Q. To what is it connected? 

A. To a pipe which leads from the signal valve as in- 
dicated (Fig. 98). 

Q. What is its use? 

A. As the signal or whistle valve (Fig. 98) operates^ the 



266 



xIir-Brake Catechis:m 



air leaving this valve escapes through the whistle (Fig. 
100). The blast signals the engineer. 

Q. Where does the air come from that supplies the 
signal system? 

A. From the main reservoir on the engine. 

Q. Explain the passage of the air from the main 
reservoir through the signal system. 



TO SIGNAL PIPE 




to whistle 
Fig. 98. — Westixghouse Signal Valve. 



A. It first passes from the main reservoir (Fig. 94) 
through the strainer and reducing valve. After leaving tlie 
reducing valve there is a tee in the pipe, one branch of whicli 
leads to the signal valve (Fig. 98), and the other back into 
the train. Under each car (Fig. 95) there is a strainer in a 
tee, and a branch of the whistle line goes to the discharge 
valve (Fig. 97). 



Air Signal System 



267 



Q. Explain the operation of the Westinghouse signal 
valve (Fig. 98) in charging. 

A. After the air passes from the main reservoir and 
through the reducing valve^ it is free to go back into the train 
and also enter the signal valve at Y, It then passes through 
the contracted port d into cavity A on top of the rubber dia- 




FiG. 99. — Westinghouse Signal Reducing Valve. 



phragm 12, and around through port c. The lower half of 
the stem 10 is three sided^ so that the air can pass up to where 
the stem looks to be tight in the bushing 9. This joint is not 
tight, but sufficiently so to allow the air to feed by into cham- 
ber B very slowly. The reducing valve is adjusted to forty 
pounds, and if we wait a short time the forty pounds will 
equalize on both sides of the diaphragm 12; that is, there 



268 Air-Brake Catechism 

will be forty pounds in each chamber A and B, as there is 
also throughout the signal pij^e on the train. 

Q. What does the conductor do if he wishes to signal 
the engineer? 

A. He pulls the signal cord in the car. 

Q. What is effected by this? 

A. It makes a sudden reduction of signal-pipe pressure 
through the car discharge valve (Fig. 97). 

Q. What is the effect on the Westinghouse valve (Fig. 
98). 

A. This starts a reduction wave throughout the signal 




Fig. 100. — Signal Whistle. 

pipe, and in the signal valve it is first felt in chamber A, 
on top of diaf)liragm 12 (Fig. 98). The pressure in cham- 
ber B, being unable to equalize quickly with that in cham- 
ber A, on account of the snug fit of the stem 10 in bushing 
9, is now greater than the pressure in chamber A. The dia- 
phragm 12 and the stem 10 attached to it are lifted, uncover- 
ing the port in the bushing 7. The stem is lifted sufficiently 
to allow air from chamber B and the air coming through port 
c to pass out at e and through the pipe to the whistle 
(Fig. 100), causing a blast as long as the stem 10 is off its 
seat. 



Air Signal System 269 

The same wave reduction that started the signal valve into 
operation also opened the reducing valve (Fig. 99) to allow 
main-reservoir pressure to supply the whistle line. 

A wave of increased pressure now takes the place of the 
reduction wave, and air passing into chamber A of the signal 
valve forces the diaphragm 12 down, causing the whistle to 
cease blowing. 

Q. How long must we wait before again trying to put 
the signal valve in operation? 

A. Until the pressures have had time to equalize in cham- 
bers A and 5 (Pig. 98). 

Q. How many seconds should we wait? 

A. Usually two at least, and three is better. 

Q. Give a rule by which we can pull the whistle signal 
cord m the car and gain the best results. 

A. When pulling the cord, make an exhaust of one second, 
and then wait three seconds to allow the whistle to cease 
blowing and the pressures to equalize throughout the signal 
system before making another reduction. 

Q. In pulling the signal cord, what should always be 
borne in mind? 

A. That it is not the amount of reduction but the sud- 
denness that causes the whistle to blow. 

Peculiarities and Troubles of the Signal System. 

Q. If no air gets into the signal pipe when an engine 
is coupled to a train, and we know that the cocks in the 
signal pipe stand properly and the hose are in order, what 
should we look at first? 

A. The plug cock in the reducing valve (Fig. 99) ; or, if 



270 Air-Brake Catechism 

the weather is cold and the reducer is outside, it may be 
frozen. 

Q. What else might cause this trouble with the reducer 
(Fig. 99)? 

A. It may be that the small taper port in the reducer 
(Fig. 99), where the main-reservoir pressure enters, is plugged 
shut or the strainer maj^ be blocked. 

Q. What will close this port? 

A. Oil from the air end of the pump and the corrosion 
from the inside of the pipes. The small ports in the reduc- 
ing valve are also sometimes closed from this cause. 

Q. What is the trouble if the signal cord is pulled in 
the car and no air issues from the car discharge valve? 

A. The cut-out cock (Fig. 95) in the saloon has very 
likely been closed. 

Q. Give conditions that would result in the air whistle 
not responding. 

A. A dirty strainer in the tee under the car where the 
branch pipe to the car discharge valve couples to the main 
signal pipe; the strainer in the car discharge valve, as used 
in the old equipment, being dirty; port d (Fig. 98) being 
stopped up; a too loose fit of stem 10 (Fig. 98) in bushing 9; 
a baggy diaphragm (Fig. 98), or a hole in it; the bowl of 
the whistle (Fig. 100) being closed with scouring material, 
or the bell of the whistle being improperly adjusted; a re- 
duction that took enough air from the signal-pipe but did 
not take it fast enough, or, as explained before, the reducer 
might be frozen. 

Q. Why would the whistle not respond if port d (Fig. 
98) were closed? 

A. Xo air could reach the whistle. 

Q. Why, with a loose fit to stem 10 (Fig. 98) in bush- 
ing 9, would the whistle not respond? 



Air Signal System 271 

A. If the reduction were not made sufficiently quick with 
the car discharge valve^ especially on a long train, the fric- 
tion of the air passing through the pipe would tend to de- 
crease the suddenness of the reduction^ so that^ when the 
wave reached the signal valve, the reduction might be so 
weak that, if stem 10 were a loose fit in bushing 9, the air 
in chambers A and B might equalize without raising dia- 
phragm 12 (Fig. 98). 

Q. Why would a baggy or stretched diaphragm (Fig. 
98) cause the whistle not to respond? 

A. When the reduction is made in the signal pipe^ a re- 
duction is made in' chamber A of the signal valve, leaving 
the pressure in chamber B greater. If the diaphragm is 
bagged^ the pressure in chamber B lifts the diaphragm^ but 
the stem is not moved. 

Q. What causes this diaphragm to bag? 

A. The use of poor rubber^, or oil from the pump work- 
ing through on the rubber, causing it to decay. A diaphragm 
is occasionally found with a hole rotted through it^ allowing 
chambers A and B to be directly connected. 

Q. What may cause a whistle to respond only once 
when the conductor pulls the cord twice? 

A. He may have pulled the cord the second time before 
the whistle stopped blowing the firsts thus getting one long 
blow^ or he may have made the second discharge before the 
pressures in chambers A and B had become equalized. 

Q. What will happen if dirt gets on the seat of valve 
4 (Fig. 99)? 

A. The valves cannot close, and we will get main-reser- 
voir pressure in the signal-pipe. 

Q. What effect has this? 

A. The whistle is likely to blow^ especially on a short train^ 
when the brakes are released; the air whistle on the engine 



272 Air-Brake Catechism 

will screech when used; and the whistle may blow two or 
three times for one reduction at the car discharge valve; 
there will be a stronger exhaust from the car discharge valve 
than usual^ and hose are more likely to burst. 

Q. Why is the whistle likely to blow when the brakes 
are released, if there is main-reservoir pressure on the 
whistle line? 

A. Because to release brakes the main-reservoir pres- 
sure is thrown into the brake-pipe. This makes the pres- 
sure in the main reservoir less than that in the signal pipe, 
and^ on account of the dirt on the seat of the valve (Fig. 99), 
the signal-pipe pressure feeds back into the main reservoir, 
and the reduction thus made in the signal pipe causes the air 
whistle to blow. 

Q. Why, with this trouble, is the whistle more likely 
to sound on an engine alone than with a train, when the 
brakes are released? 

A. With an engine alone there is but a small volume 
of air on the signal line, and the signal-pipe pressure feed- 
ing back into the main reservoir would cause a more sudden 
reduction than if the signal pipe were longer and the vol- 
ume greater, as on a train. 

Q. Why will the air whistle on the engine screech 
when used? 

A. Because the bell is adjusted to be used with only a 
forty-pound pressure instead of ninety or more. 

Q. Why is the whistle likely to blow two or three 
times with one reduction from the car discharge valve, if 
main-reservoir pressure is in the signal pipe and the stem 
10 is loose in bushing 9 (Fig. 98) of the signal valve? 

A. Because a reduction at the car discliarge valve starts 
the signal valve in operation, and the reducer cannot feed 
air into the signal pipe properly to cause the signal valve 



Air Signal System 273 

to close until the signal-pipe pressure is below forty pounds. 
The tendency for the pressure to fluctuate in chambers A 
and B, due to the loose fit of the stem 10, causes the dia- 
phragm to bounce and the whistle to respond two or three 
times. 

Q. If an engineer wishes to know how much pressure 
he has in his signal pipe, and he has no gage with which 
to test it, how can he determine it? 

A. Shut off the pump and open the bleed cock on the 
main reservoir^ then get up in the cab and watch the red 
hand. When the whistle blows^ the red hand represents a 
trifle less pressure than is being carried in the signal pipe. 

Q. Why does the whistle blow? 

A. Because, when the main-reservoir pressure is drained 
below the pressure in the signal pipe, the pressure feeds from 
the signal pipe back into the main reservoir, causing a re- 
duction of the signal-pij)e pressure, and this usually causes 
the whistle to blow. 

Q. What is likely to make a whistle give one long 
blast? 

A. A tight fit in bushing 9 of stem 10 (Fig. 98). 

Q. What will cause a whistle to sing constantly? 

A. Dirt on the seat of stem 10 in bushing 7 (Fig. 98). 
Q. Why may jars cause a whistle to blow? 

A. Oil baking upon the diaphragm of the signal valve 
makes it rigid, and a jar will sometimes shake the stem from 
its seat. 

Q. What would we do with the reducer (Fig 99) to 
increase or decrease the pressure in the signal pipe? 

A. Screw up on the bottom nut to increase it, and down to 
decrease it. 



CHAPTEE IX. 

BRAKING POWER AND LEVERAGE 

Q. What is meant by braking power? 

A, The force applied by the shoes against the wheels to 
stop the motion of a car. 

Q. What is meant by the percentage braking power? 

A. The total brake-shoe pressure as compared to the light 
weight of the car. The percentage is found by dividing the 
total braking power by the light weight of a car. 

Q. How is the braking power determined? 

A. By assuming a definite air pressure in the brake cyl- 
inder, and computing the total force developed against the 
wheels by the shoes due to this pressure acting against the 
brake cylinder piston. Formerly the maximum air pressure 
that could be obtained in the cylinder, was used as a basis 
of calculation ; but since, with 70 pounds in the brake-pij)e, a 
plain triple valve obtains 50 pounds maximum cylinder pres- 
sure, a quick-action triple valve 60 pounds pressure, the ET 
equipment G5 pounds pressure, etc., it is now the custom to 
use 50 pounds C3dinder pressure uniformly as a basis of 
calculation of braking power in all classes of equipment. All 
percentages given below are based on a 50-pound cylinder 
pressure. 

Q. What per cent of the light weight is used as brak- 
ing power on a freight car using 50 pounds cylinder-pres- 
sure as a basis of calculation? 

A. Sixty per cent or six-tenths of the light weight of the 
car. 



Braking Power and Leverage 275 

Q. On a passenger car? 

A. Eighty per cent or eight-tenths of the light weight of 
the car^ excepting with the new high-speed brake (type L 
triple valve and supplementary reservoir)^ when ninety per 
cent is used. 

Q. Can these percentages be used if the car has two 
six-wheel trucks, and only two pairs of wheels on each 
truck are braked? 

A. No; the percentages given refer to a certain per cent 
of the total weight on the rails of the hrahed wheels. If only 
two pairs of wheels are braked on each truck, and the car rests 
equally on all six pairs of wheels^ it is clear that the weight 
of the car that is supported by the braked wheels is only four- 
sixths of the total weight of the car. Therefore in such a 
case, eighty per cent (or ninety) of four-sixths (or two- 
thirds), of the total light weight of the car should be used 
as the braking power. Or, which is the same thing, use 2/3 of 
the percentages; 53 1/3 per cent (or 60 per cent) of the to- 
tal light weight. 

Q. What per cent braking power is used in designing 
driver brakes? 

A. With the old standard equipments, seventy-five per 
cent or three-fourths of the weight on the drivers when the 
engine is ready for the road. With the No. 6 ET equipment, 
sixty per cent of the same weight is used. 

Q. What per cent braking power is used on engine 
truck or trailer- wheel brakes? 

A. With the old standard equipment sixty per cent; with 
the No. 6 ET equipment, forty-five per cent — of the weight 
of the engine in working order on them, in each case. 

Q. What per cent braking power is used on tenders? 

A. With old standard passenger tenders, or freight ten- 
ders equipped with quick-action triple valves, 85 per cent 



276 Air-Brake Catechism 

of the light weight; with old standard freight tenders hav- 
ing plain triple valves^ 100 per cent is used; with tenders 
equipped with Xo. 6 ET Equipment, 80 per cent is used. 

Q. Why is a larger per cent braking power used on 
tenders than on engines or freight cars? 

A. Because tenders are practically always loaded. 

Q. How were these percentages determined on as safe? 

A. By actual tests in the different kinds of service. 

Q. What brake-cylinder pressure is used in figuring 
the braking power with the different sizes of cylinders? 

A. Fifty pounds. 

Q. How do we calculate the force acting on the push 
rod due to the pressure in the cylinder acting on the 
piston? 

A. Multiply the diameter of the piston by itself; the 
product by the decimal .7854, and this last product by the 
air pressure in the brake cylinder. 

Q. What force would act on the push rod of an 8-inch 
cylinder? 

A. 8 X 8 X .7854 X 50 = 2513, usually figured as 2500 
pounds. 

Q. Explain the difference in the percentage braking 
power of a freight car light, and the same car when 
loaded to its full capacity. 

A. Sixty per cent of the light weight of a freight car is 
considered safe braking power. 

If the light weight of a freight car is 40,000 pounds, it is 
given 24,000 pounds braking power. If the capacity of the 
car is 100,000 pounds, when loaded to its full capacity the 
total weight of the car and contents is 40,003 + 100,000, or 
140,000 pounds, but we have only the brake-shoe pressure 
to stop the car loaded that is used when it is light. 

In full service application we obtain fifty pounds pressure 



Braking Power and Leverage 277 

in the brake cylinder. This gives sixty per cent braking power 
when the car is lights but when the car is loaded^ the per- 
centage of braking power to the total weight of the car 
and contents is only seventeen per cent. 

In emergency^ we get about sixty pounds pressure in the 
brake cylinder which amounts to seventy-two per cent braking 
jDower w^ith a light car; but with the car loaded, when the 
brakes are set in emergency, the braking power is about twen- 
ty and one-half per cent of the total weight of this car. 

Q. How is the percentage braking power of a pas- 
senger car affected by its load? 

A. l^fot very niuch^ because eighty per cent of the light 
weight of the car is used as braking power^ and when loaded, 
the additional weight is seldom as much as 10,000 pounds. 

-^ — i^ ^ — 





LEVER OF 1st KIND 
Fig. 101. 

Q. What forces are usually figured as acting at the 
push rod with the different sized cylinders, the cylinder 
pressure being figured at fifty pounds in service and sixty 
in emergency with the quick-action triple, and fifty 
pounds with the plain triple in either service or 
emergency? 

A. Service application: 
6 in. 8 in. 10 in. 12 in. 14 in. 16 in. 18 in. 
1400 2500 4000 5600 7700 10,000 12,200 

Emergency application : 
1700 3000 4700 6800 9200 12,000 14,700 

By using the following cuts and formula?, the braking 
power on a car with any kind of leverage may be figured. 



278 



Air-Bkake Catechism 



There are three classes of levers: 

I. When the fulcrum c (Figs. 101 and 102) is between 
the force F and the weight IF. 

II. When the weight W (Figs. 103 and 104) is between 
the force F and the fulcrum c. 

III. When the force F (Figs. 105 and 106) is between 
the weight W and the fulcrum c. 

Figs. 101 and 102 represent a lever of the first class. 

Q. What brake-shoe pressure W will result with a 
force F = 2500 pounds, b = 16 inches, a = 8 inches? 

FX'b 2500 X 16 



A. F 



or W 



or F = 5000 



a 8 

pounds. 

The forces W and F act in the same direction on the levers^ 
and the force at c acts on the lever in an opposite direction 
from both and must be equal to their sum^ or 7500 pounds. 

Q. What is the distance a if F = 2500, b = 16 inches, 

and W = 5000? 

FXh 

; substituting values. 



A. a = 



W 



a 



2500 X 16 

5000 



or a = 8 inches. 



Q. What is the force F, when W = 5000, a 
and b = 16 inches? 

F X a 
A. 2^ = — ; substituting values, 



8 inclies, 



F = 



5000 X 8 
16 



OY F = 2500 pounds. 



Q. How do we find b if W = 5000 pounds, F-=:2500 
pounds, and a = 8 inches? 



BiiAKiNG Power and Leverage 



379 



W Xa 



A. J) = 



; substituting values. 



5000 X 8 , ^n ■ I. . 
J, or 6 = 16 inches. 

" "~ 2500 



Figs. 103 and 101 represent levers of the second class with 
the weight between the fulcrum c and the force F. 




FORMULA 



--Fxb 
^~ W 

. Wx.a 



Fig. 102. — Lever of 1st Kind. 

Assume that F = 2500 pounds, a -= 8 inches, d 
inches, and 5 = a + <?. or 24 inches. 
Q. What is W? 

F X b 

A -yy _- • substituting values, 

a 



= 16 



^Y ^^^^O^l^f or W = 7500 pounds. 

In this class of levers we see that the forces F and F act 
in opposite directions on the lever, and the force exerted at c 
will be equal to the difference between F and F, or 5000 

pounds. 

We may compute values for a, F or h, as was illustrated m 



280 Aie-Brake Catechism 

the first class of levers, if we know the values of the other 
three. 

Figs. 105 and 106 represent the third class of lever with 
the force F exerted between the weight 17 and the fulcrum 
c. 

Assume that F = 2500 pounds, & = 8 inches, (i = 16 
inches, a = & + <^^ or 2-^- 

Q. What is W? 

F X l 
A. IF = ; substituting values, 

2500 X 8 
W = -^ or TF = 833 1/3 pounds. 



d- 



LEVER0F2NDKLMD 

Fig. 103. 





TF and F act in opposite directions on the lever in this case, 
and the force exerted at the fulcrum c will be eqilal to the 
difference between F and ^Y, or, in this case, 1666 2/3 pounds. 

The other three formulae may be used to find the value of 
a, F or b when the other three values are known, as already 
shown. 

Besides speaking of levers as first, second, and third class, 
they are known by their proportions as 1 to 1, 2 to 1, 2l^ to 
1, etc., according to the amount the force F is raised or di- 



Brakixg Power and Leverage 



281 



minished^ due to the class and proportions of the levers em- 
ployed. 

To find the proportion of a lever of the iirst class, divide 
the distance of the fulcrum c to the force F by the distance 




FORMULAE, 



^^ a 



Wxa 



n-Fxb 

w 



Wxa 



Fig. 104. — Levee of 2xd Kind. 




d-- 





LEVEROFSrdKIND 



Fig. 105. 




W= 



FORMULA 
Fx b 



F — Wxa 

b 



Fxb 



W 



h^ Wxa. 
b— p-^ 



Fig. 106, — Lever of 3rd Kind. 



282 Air-Brake Catechism 

from the fulcrum c to tlie weight W; or, referring to Fig. 
101^ it would be: 

& -^- a or 16 ^- 8 = 2. This proportion of lever would l)e 
called a 2 to 1 lever. 

The force F is multiplied by 2 at W. 

In the second class, or Fig. 103^ the proportion of the 
lever would be represented by: & -f- a or 2-1: -f- 8 ^= 3, or a 3 
to 1 lever. 

In the third class^ or Fig. 105^ the jDroportion of the lever 
would be represented by: 6 -^ a or 8 -^ 24: = 1/3. or a 
1/3 to 1 lever^ in which case the proportion and class of levers 
reduces the force 3 to 1 instead of increasing it. 

Having studied the classes of levers, we will now make a 
practical application of their use in figuring the proportion 
of the levers to be applied to a car of given weight. 

We wish to design a brake for a passenger car, the weight 
of which is 60,000 pounds, and use the Hodge system of 
levers as shown in Fig. 107. 

Eighty per cent, or eight-tenths of 60,000 pounds is 48,000 
pounds. 48,000 pounds will be the braking power to apply 
to the wheels of a passenger car weighing 60,000 pounds. 

48,000 -f- 4 = 12,030, or the amount of braking power to 
be developed at each brake beam. 

The length of the truck levers has to be determined from 
the truck construction. We will suppose the dimensions to 
be — long end, 28 inches; short end, 7 inches. 

The truck levers are of the second class and substituting 
tlie values in the formula (Fig. 104). 

^^ X ^ 12,000 X 7 

F = ~"7 or 7^ = ^— — — or F = 2400 

^ 3o 

That is, to get a power IF of 12,000 pounds against the 
brake beam, a force of 2^400 poi^nd^ is necessary at the top 
of the live truck lever. ' 



Braking Power and Leverage 



283 



The forces F and ^Y act on the live lever in opposite direc- 
tions^ so the force acting at fulcrum c will be 12^000 — 2400 
= 9.600. This power is transmitted to the bottom of the 
dead lever^ which is of the same class as the live lever; but 
the force F is applied at the bottom instead of the top of 
the lever. 

We have from Fig. 104 : 



W = 



FXh 



or W = 



a 



9,600 X 30 
24 



or W = 12,000 



So that;, with a force of 2^400 pounds acting at the top 



TO HAND BRAKE 



5600 LBS 
10400 LBS 





([TsAME AS 
^OTHER END 



28" d 1 



HODGE SYSTEM 



Fig. 107. 



of the live lever of the dimensions given, a power W of 12,000 
pounds is developed at each truck brake beam. 

The dead truck lever need not be of the same length as the 
live lever, but the proportions between the holes must be the 
same in each. 

The force of 2,400 pounds that acts on the top of the live 
lever also acts at X, the end of the floating lever^ and we must 
now determine what force must act on the rod that con- 
nects the end of the cylinder lever with the floating lever. 

This rod is connected at the middle of the floating lever. 



284 Air-Brake Catechism 

and the power at this point must be sufficient to develop a 
force of 2^400 pounds at each end of the floating lever. 

The force exerted at the middle must be 2 X 2,400 or 
4^800 pounds, as half of this amount is given to each end of 
the floating lever. 

This 4^800 pounds acting at the center of the floating lever 
must also act at the end of the cylinder lever^ being connected 
directly with it. 

What we now wish to determine is, with any desired length 
over all, how must the holes be sj)aced in the cylinder lever 
that the pressure acting on the push rod will j)roduce a force 
of 4,800 pounds at the outer end of the cylinder lever. 

With any brake equipment except the new high-speed brake^ 
a 12-inch cylinder is recommended by the Westinghouse 
Company to be used with this weight of car. With a 50-pound 
cylinder pressure, the 12-inch cylinder gives a push at the 
piston rod of 5,600 pounds. We will suppose the distance 
between the outside holes of the cylinder lever to be 30 
inches. 

The following rule will enable us to locate the middle hole 
in the cylinder lever to which the tie rod is attached. 

Multiply the force acting at the piston hy the length of the 
lever between the outside holes, and divide the product hy the 
sum of the forces acting at both ends of the cylinder lever. 
The result will be the distance from the middle hole of the 
cylinder lever to the hole to luhich the connection running to 
the floating lever is attached. 

Applying this rule to our problem we have 
5,600X30= 168,000 
5,600 + 4,830 = 10,400 
168,000 -f- 10,400 = 16.15 
30 — 16.15 =13.85 

The distance between the holes at the short end is 13.85 
and the long end 16.15 inches, and, according to tJie rule, the 



Braking Power and Leverage 285 

long end is connected to the connection running to the float- 
ing lever. 

The force exerted at the middle hole of the cylinder lever 
is also communicated to a hole similarly placed in the other 
cylinder lever^ so, that, using the same levers, we will obtain 
the same braking power on the wheels of the other truck. 

In figuring the levers for the Stevens system of leverage, 
the power desired at the top of the live lever is figured the 
same as just explained. 

When we know this force, we know that the same power 
has to exist at the outer end of the cylinder lever, as the 
Stevens system has no floating lever. 

This we figure by the rule already given for spacing the 
holes in the cylinder levers. 

To figure the braking power of a car already equipped, we 
start with the force acting on the piston rod and Avork to- 
wards the truck levers by the aid of the formulae given. 

To use the formulae, first determine the class of lever with 
which we have to deal. 

The foregoing illustrations were practical applications of 
the formulae, in calculating the proportion of levers that 
would give a proper braking power on a car of known weight. 

We will now consider a shorter method of calculating 
the proportion ' of levers for a Hodge and for the Stevens 
systems of leverage for this same car. 

Fig. 107 (page 283) shows the Hodge system of levers. 
If this were a Stevens system, the floating lever would not 
be used, and the other end of the connection to the live lever 
of the truck would connect directly with the outer end of 
the C3dinder lever. With the Stevens system tlie hand-brake 
connection runs from the brake mast direct to the top of the 
dead lever. 

(1.) To find the total brahtng power required: 

For any equipment except the new high-speed brake, sub- 



286 Air-Brake Catechism 

tract 20 per cent, of the weight of the car on the wheels to 
be braked for passenger cars^ and 40 per cent, for freight 
cars. For passenger cars with the new high-speed brake, 
subtract 10 per cent. 

(2.) To find the total leverage required: 

Divide the total braking power required by the total pres- 
sure on the piston, 50-pound cylinder pressure taken as a 
basis of calculation. The total leverage should usually not 
exceed 9 to 1. 

(3.) To find the proportion of the hraJce-beam levers: 

Divide the entire length of the lever by the short eird, if 
the truck has a bottom connection; if it has a middle con- 
nection^ divide the long by the short end. 

(4.) To find the total braJce-beam leverage: 

Multiply the proportion of the brake-beam levers by two, 
for the Hodge system, and by four for the Stevens system. 

(5.) To find the proportion of the cijlinder lever: 

Multiply the whole length of the lever by the required total 
leverage and divide the product by the sum of the total 
brake-beam leverage plus the required total leverage. 

If the required total leverage is greater than the total 
brake-beam leverage, the long end of the lever must go next 
to the cylinder ; if less, the short end goes next to the cylinder. 

The dead and live truck levers may be of different lengths, 
but must be of the same proportion to develop the same 
braking power. 

EXAMPLE. 

Hodge system of levers, as shown on page 283, also the 
lengths of the truck levers. 

Weight of car, 60,000 lbs. Old-style standard brake equip- 
ment used. 

A 12-inch cylinder is used with this weight of car. 

A pressure of 5,600 lbs. is developed on a 12-inch piston, 
using 5 3 -pound cylinder pressure as a basis. 



Brakixg Power and Leverage 



287 



(1.) 60,003 lbs. less 20 per cent, is 48,000 lbs. 
(2.) 48,000 lbs. -f- 5,600 = 8.57, total leverage required. 
(3.) 35-f-7 = 5, brake-beam leverage. 
(4.) 5X2=10, the total brake-beam leverage. 
Assume the length of the outside holes of the cylinder 
lever to be 30 inches. 

(5.) (30 X 8.57) -^ (8.57 + 10) = 13.85 inches. 
33 — 13.85 = 16.15 inches. 




STEVENS SYSTEM 

OF 

CAR BRAKE LEVERS 



Fig. 108. 




HODGE SYSTEM 

OF 

CAR BRAKE LEVERS 

Fig. 109. 




TENDER BRAKF- 
LEVERS 

Fig. 110. 



288 Aie-Brake Catechism 

The required leverage is less than the total brake-beam 
leverage, hence the short end of the cylinder lever connects 
to the piston. 

Stevens system — same car. 

(1.) 60,000 lbs. less 23 per cent, is 48,000 lbs. 

(2.) 48,000 -f- 5,600 = 8.57, total leverage required. 

(3.) 35-^-7 = 5, the brake-beam leverage. 

(4.) 5 X 4 = 20, the total brake-beam leverage. 

The cylinder lever is 30 inches between outside holes. 

(5.) (30 X 8.57) -f- (20 + 8.57) = 9 inches. 

30 — 9 = 21 inches. 
The required leverage is less than the total brake-beam 
leverage, hence, according to the rule, the short end of the 
cylinder lever (9 inches) connects to the piston. 

Q. Give a rule by which the braking power on prac- 
tically any engine, tender or car can be calculated. 

A. Multiply the force acting by the distance from the 
force to the fulcrum, and divide this product by the distance 
from the work to the fulcrum; the result will be the work 
that can be accomplished. 
In this rule let F = force, 
^y = work, 
a = distance from the point at which the 

force is applied to the fulcrum, 
h = distance from the fulcrum to the 
point at which the work is to be 
accomplished. 
Then we have the following formula which can be used: 



Q. What must be determined to use this rule intelli- 
gently? 

A. It must always first be determined which jDoint on any 



Braktn^g Power and Leverage 



289 



lever is the fulcrum. For instance, in considering the piston 
lever (Fig. 107) the fulcrum is the rod which connects the 
piston and cylinder levers when we wish to ascertain the 
amount of work that can be done at the outer end of the 
piston lever. If we wish to ascertain the amount of work 
that can be done on the rod connecting the piston and cylinder 
levers^ the fulcrum would then be the outer pin in the pis- 
ton lever. 

To find the work accomplished on the brake shoes connected 
to the live truck levers (Fig. 107)^ the lower pin of the live 
lever is the fulcrum; but if we wish to know what work is 
done on the bottom truck connection by a force acting on the 




Fig. 111. — Americats^ Equalized Brake. 



top of the live lever, the point at which the brake shoe is 
shown represents the fulcrum. 

What has been said on the subject of brake leverage in this 
chapter is all useful, and a thorough understanding of it 
will enable one to make many short cuts in leverage problems 
presented for consideration, but the last very simple rule will 
be found to be sufficient with which to calculate the braking 
power in practically any system of leverage. 



290 Air-Brake Catechism 

Sizes of Cylinders to be Used on Cars and Tenders of 
THE Following Maximum Light Weights, 
AS Recommended by the Westing- 
house Air-Brake Company. 

passenger cars. 

standard Equipments, 
Size of Cylinder. Including Old Style New Style High-speed 

High-speed Brake. Brake Equipments. 

8" 16,000 to 28,000 16,000 to 25,000 

10" 28,000 to 44,000 25,000 to 39,000 

12" 44,000 to 63,000 39,000 to 56,000 

14" 63,00a to 86,000 56,000 to 77,000 

16" 86,000 to 113,000 77,000 to 100,000 

18" 113,000 to 143,000 100,000 to 137,000 

FREIGHT CAES. 
Size of Cylinder. Any Freight Equipment. 

8" 22,000 to 37,000 

10" 37,000 to 58,000 

tenders. 



-Old Standard Equipment, 



Size of With (iuick-action With Plain 

Cylinder. Triple Valve, Triple Valve. E T Equipment. 

8" 15,000 to 26,000 15,000 to 22,000 15,000 to 28,000 

10" 26,000 to 41,000 22,000 to 35,000 28,000 to 44,000 

12" 41,000 to 59,000 35,000 to 50,000 44,000 to 63,000 

14" 59,000 to 81,000 50,000 to 69,000 63,000 to 86,000 

16" 81,000 to 106,000 69,000 to 90,000 86,000 to 113,000 

American Brake Leverage. 

Q. How do you find the braking power on an engine 
equipped with the American equalized brake as shown in 
Fig. Ill, page 289? 

A. Multiply the cylinder value, or total push on the pis- 
ton, by the long lever arm, and divide this product by the 



Braking Power and Leverage 291 

short lever arm. This result multiplied by 2 gives the total 
braking power. 

Q. With the long lever arm 25 inches long and the 
short arm 5, what braking power would we have, using 
12-inch cylinders? 
A. 56,000 pounds. 
Thus: 

5,600 X 25=: 140,000 

140,000 -f- 5= 28,000 

28,000 X 2= 56,000 

Q. If any different design of rigging were used than 
that shown in the sketch, how could the braking power 
be figured? 

A. First find the power exerted at the bottom of tlie 
rocker shaft and use this in connection with the cuts il- 
lustrating the different classes of levers. 

Q. What per cent of the total weight on drivers is 
used as braking power with driver brakes? 

A. Seventy-five per cent of the engine's weight on the 
drivers when ready for the road, when the old standard 
equipment is used, and sixty per cent when the ET equip- 
ment is used. 

Q. What braking power should be used on an engine 
whose weight on drivers is 90,666 pounds, using the old 
standard brake equipment? 

A. 90,666 X .^5 = 68,000 pounds. 

Q. What weight should be on the drivers for an engine 
to have 68,000 pounds braking power, using the old stand- 
ard brake equipment? 

A. 68,000 -^ .75 = 90,666 pounds. 

Q. How should the holes be spaced in levers A and D 
on an engine having two pairs of drivers, to give an equal 
braking power on each wheel? 



292 Air-Brake Catechism 

A. The middle hole in A should be equidistant from the 
two outside ones. The hole in the lever at D should be so as 
to have the connection attached at fc stand about parallel 
with the track. The corresponding hole k at the other end 
of the lever D must be jDlaced the same distance from the 
other end. 

Q. How should the holes be spaced in levers A, B and 
D, if on a mogul or engine having three pairs of drivers? 

A. The distance c, lever A, should be one-half the dis- 
tance f. The distance g, lever B should be equal to h. The 
hole K, lever D, should be the same as on an engine having 
two pairs of drivers. 

Q. How should the holes in the levers A, B, C and D be i 
spaced on a consolidation or engine with four pairs of | 
drivers? 

A. The distance e in lever A should be one-third of f,\ 
The distance g, lever B, should be one-half of h. The dis- 
tance i, lever C, should be equal to ;'. The hole h in leverl 
D should be the same as with an engine having two or threel 
pairs of drivers. 

CAM BEAKE. 

The following simple rule to find the braking power de- 
veloped by a cam brake is given by Mr. H. A. Wahlert. 

Take two wires and place them between the brake sho( 
and the wheel; one at the top and one at the bottom of th( 
shoe. Apply the brakes fully, and then measure the pistoi 
travel. Now release the brakes, recharge, remove the wires] 
and tlicn apply fully again. Measure the piston travel again] 
and note how much more it has increased. Divide tlie addi- 
tional travel had upon removing the wires b}^ the thickness 
of the wire, and multiply this by the value of the cylinderj 
The result is the braking power on each brake shoe. 



Air Hose 293 

Four times this power is the total braking power developed 
on all four shoes. 

EXAMPLE. 

Thickness of wires, % inch. 

Piston travel, with wires inserted according to rule^ 3 
inches. 

Piston travel, with wires removed, 3^/^ inches. 

Value of 8-inch cylinder, 2,500 pounds. 

3% inches — 3 inches = i/^ inch. 

y^ iiich -i~ i/s inch = 4. 

2,500 pounds X 4 = 10,000 pounds on each brake shoe. 

10,000 pounds X -i = 40,000 pounds on all four brake 
shoes. 

AIE HOSE. 

Q. What kinds of hose are used in the air brake and 
signal systems? 

A. Usually one-inch hose is used with signal equipment 
on cars in passenger, mail, and express service; while inch 
and three-eighths hose is used exclusively in freight service. 

Q. Is this a standard on all roads? 

A. Xo; some roads use the inch and three-eighth hose 
with the brake equipment in both freight and passenger ser- 
vice. 

Q. Would there be any objection to using one-inch 
hose in freight service? 

A. The chief objection consists in the fact that the small 
hose presents a greater frictional resistance to the passage 
of air. This would be especially objectionable when it was 
desired to make a quick reduction to apply the brakes in quick 
action. 

Q. What is the object of having different hose 
couplings for the air and signal hose? 



294 Aie-Brake Catechism 

A. So that brakemen^ when in a hurry, cannot couple 
the brake and signal hose together ; some companies paint the 
signal hose coupling red as a further aid when coupling hose. 

Q. How many cars of air are coupled up and operated? 

A. Some roads regularly couple as high as 115 cars and 
operate the brakes with the air supplied by a nine and one- 
half inch pump. 

Q. Could this be done with a poor hose? 

A. So, since with poor hose there is often considerable 
leakage not discernible with the naked eye. 
Q. How may porous hose be detected? 
A. By coating the outside with soapsuds. 
Q. What is the usual life of air hose? 

A. Passenger, about two and one-half years; freight, 
about two years. 

Q. How is air hose bought? 

A. Some on account of cheapness, some by a time guar- 
antee, and others by specification, the roads being willing to 
assume the risk in the latter case if they know the hose to 
be first-class when put in service. 

Q. What is the object of the markings shown on the 
hose (Fig. 112)? 

A. It is for the purpose of obtaining a record of the 
life of the hose. The one applying the hose should cut off 
the figure representing the month, in the line headed by the 
letter A, and the figure which shows the year. When the hose 
is removed the year and month should also be shown by cut- 
ting off the proper numbers. 

The following specifications have been recommended by 
the ^Master Car Builders' Association. They have been in force 
for some time on the raih^oads throughout the country, and 
constitute a definite standard for interchange. 



Air Hose 



295 



AIR-BRAKE AND SIGNAL-HOSE SPECIFICATIONS ISSUED BY THE 
MASTER CAR BUILDER's ASSOCIATION IN 1905. 

1. All air-brake hose must be soft and pliable^ and not less 
than two-ply nor more than four-ply. They must be made 
of rubber and cotton fabric^ each of the best of its kind made 
for the purpose. No rubber substitutes or short-fibre cotton 
to be used. 



NAME OF ROAD 



u» 



09 



03 
04 
05 
06 
07 



A 



R 



12345 6 
7 8 9 10 1112 

12345 6 
7 8 9 10 IM2 



CO 



NAME OF MANUFACTURER 



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(0 

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Fig. 112. — Standard Label for Air Hose. 

2. The tube must be hand-made, composed of three cal- 
endars of rubber. It must be free from holes and imper- 
fections, and in joining must be so firmly united to the cotton 
fabric that it can not be separated without breaking or split- 
ting the tube. The tube must be of such composition and 
so cured as to successfully meet the requirements of the 
stretching test given below; the tube to be not less than 3/32 
inch thick at any point. 

3. The canvas or woven fabric used as wrapping for the 
hose to be made of long-fibre cotton, loosely woven, and to be 
from 38 to 40 inches wide, and to weigh not less than 23 and 
22 ounces per yard, respectively. The wrapping must be 



296 Aie-Brake Catechism 

frictioned on both sides, and must have^ in addition, a dis- 
tinct coating or layer of gum between each ply of wrapping. 
The canvas wrapping must be applied on the bias. Woven or 
braided covering should be so loose in texture that the rubber 
on either side will be firmly united. 

4. The cover must be of the same quality of gum as the 
tube, and must not be less than 1/16 inch thick. 

5. Hose is to be furnished in 22-inch lengths. Variations 
exceeding ^4 i^ch in length w^ill not be permitted. Eubber 
caps not less than 1/16 inch nor more than % inch must 
be vulcanized on each end. 

6. The inside diameter of hose must not be less than 1% 
inches nor more than 1 7/16 inches, nor must the outside dia- 
meter exceed 2% inches. Hose must be smooth and regular 
in size throughout its entire lengthy except at a point 2^ 
inches from either end, where the inside calendar of rubber 
may be increased 1/16 inch for the distance of y^ inch 
toward either end and then tapering to regular diameter. 

7. Each length of hose must have \ailcanized to it a badge 
of white or red rubber as shown. On the top of the badge 
the name of the purchaser ; on the bottom the maker's name ; 
on the left-hand end the month and year of manufacture, 
and on the right-hand end the serial number and the let- 
ters ''M. C. B. Std.'' These letters and figures must be clear 
and distinct, not less than 3/16 inch in height, and stand 
in relief not less than 1/32 inch, so that they can be removed 
by cutting without endangering the cover. Each lot of 200 
or less must bear the manufacturer's serial number, com- 
mencing at (1) on the first of the 3'ear, and continuing 
consecutively until the end of the year. 

For each lot of 200, one extra hose must be furnished free 
of cost. 

S. Test hose will be subject to the following tests; 



Air Hose 



297 



BURSTIXG TEST. 

The hose selected for test will have a section five (5) inches 
long cut from one end and the remaining seventeen (17) 
inches will then be subjected to a hydraulic pressure of 100 
pounds per square inch, under which pressure it must not ex- 
pand more than 14 inch nor develop any small leaks or de- 
fects. The section will then be subjected to a hydraulic pres- 
sure of 400 pounds per square inch for ten 
minutes, without bursting. 

FKICTION TEST. 

A section one (1) inch long will be taken 
from the five (5) inch piece previously cut 
off, and the quality determined by suspend- 
ing a 20-pound weight to the separated end, 
the force being applied radially, and the time 
of unwinding must not exceed eight (8) 
inches in ten minutes. 

■p^^ -j^-1^3^ STRETCHING TEST. 




Another section one (1) inch long will be cut from the 
balance of the five (5) inch piece, and the rubber tube or lin- 
ing will be separated from the ply and cut at the lap. Marks 
two inches apart will be placed on this section, and then the 
section will be quickly stretched until the marks are eight 
(8) inches apart and immediately released. The section will 
then be re-marked as at first and stretched to eight (8) inches 
and will remain so stretched ten (10) minutes. It will then 
be released, and ten (10) minutes later the distance between 
the marks last applied will be measured. In no case must 
the test piece break or show a permanent elongation of more 



298 Air-Brake Catechism 

than 1/4 inch between the marks last applied. Small strips 
taken from the cover or friction will be subjected to the same 
tests. 

9. If the test hose fails to meet the required tests, the lot 
from which it was taken may be rejected without further ex- 
amination and returned to the manufacturer who shall pay 
the freight charges in both directions. If the test hose is 
satisfactory the entire lot will be examined, and those com- 
plying with the specifications will be accepted. 



CHAPTEK X. 

THE SWEENEY COMPRESSOR 

Q. What is the object of the Sweeney device? 

A. To recharge a main reservoir quickly in descending 
very heavy grades when the air pressure is low. 

Q. Explain the parts. 

A. It consists of a pipe running from the steam chest to 
the main reservoir. In the pipe there is a cut-out cock, a 
safety valve^ and a non-return check. 

Q. How is it operated? 

A. By turning the cut-out cock and reversing the engine 
when steam is shut off. The main cylinders and pistons act 
as compressors^ and compressed air is forced into the steam 
chest and thence through the pipe connection to the main res- 
ervoir. 

Q. What is the objection to this device? 

A. It is extremely handy in case of emergency, such as 
low pressure or the refusal of a pump to work. The objec- 
tion to it is^ that smoke, gas, and heat forced into the main 
reservoir burn out gaskets and get the brake system very dirty. 

THE WATER BRAKE. 

Q. What is the Water or La Chatelier Brake? 

A. It is a brake by means of which the equivalent effect 
of reversing an engine is produced; that is, the back pres- 
sure on the pistons acts through the pins the same as when 
using steam. 



300 Aie-Brake Catechis]m 

Q. Is water actually used at the point where the work 
of retardation is accomplished? 

A. Xo^ it is then in the form of wet steam. 

Q. Where does the water used come from? 

A. It is taken from the boiler just above the crown sheet. 
The pressure from above being removed as soon as it leaves 
the boiler it flashes into wet steam. The compression to which 
it is subjected in the cylinders produces heat that also tends 
to change any water into steam. 

Q. Is the lubricator shut off when the water brake is 
in use? 

A. Xo, it should be kept in operation the same as when 
using steam. 

Q. What special care should be taken when using 
steam after the use of the water brake has been dis- 
continued? 

A. To avoid throwing water out of the stack, steam should 
not be used until the water has had ample time to work out. 

Q. Can a water brake be used on either a simple or 
compound engine? 

A. Yes; Fig. Hi shows its application to a simple and 
Figs. 115 and 116 to a compound engine. 

WATER BRAKE OX SIMPLE EXGIXE. 

Q. What part does the water play after it takes the 
form of wet steam? 

A. As the pistons move back and forth the wet steam in 
the exhaust cavities (Fig. 114) is drawn into the C3dinders. 

Q. How does it escape from the cylinders? 

A. Through the cylinder cocks. 

Q. If it were not for the wet steam being drawn into 
the cylinders when the engine is reversed, while using 
the water brake, what would happen? 

A. Cinders and smoke would be drawn into the cylinders 



The Water Brake 



301 



and in a sliort time they would be cut and ruined. 

Q. How should an engineer proceed to put the water 
brake in use? 

A. The C3dinder coeks should first be opened and should 




Fig. 114. — Water Brake on Simple Engine. 



302 Aik-BPvAke Catechism: 

remain open as long as the water brake is in use ; the reverse 
lever should be moved back of the center the desired amount 
and the globe valve (Fig. Hi) should be opened immediately. 

Q. When should the water brake be put in use? 

A. When the train is moving slowly. 

Q. At how fast a speed is it practical to operate a 
water brake? 

A. It is not generally used at speeds in excess of 1-i to 
22 miles per hour. 

Q. How far should the reverse lever be moved back 

of the center? 

A. This depends upon the amount of work that is required. 
The farther back the lever is moved the greater the power. 

Q. How much should the globe valve (Fig. 114) be 
open to obtain the right amount of steam in the cylin- 
ders? 

A. It should be adjusted until the steam issuing from 
the cylinder cocks is a dense white. 

Q. What will be the character of escaping steam at 
the cylinder cocks if too little water is being used? 

A. It will be a lioht blue in color. 

i_ 

Q. How can it be told if too much water is being 
used? 

A. Water will be thrown out of the stack. This is es- 
pecially noticeable if the lever is very near the center. 

Q. What is the purpose of the 1-32-inch hole drilled in 
the y2X%-inch tee, as indicated (Fig. 114)? 

A. To permit any condensation to escape. 

Q. In erecting the piping what special care should be 
observed? 

A. C'are should be exercised to locate the % " ^ %" ^^^ 
in the center to insure the same amount of water reaching 



The Water Brake 



303 



each cylinder; otlierwise the tendency would be for one side 
of the locomotive to furnish more retarding power than the 
other. 



^Rod to c lb, to operate exhaust lid 




Rod to cab, to operate 
back pressure valve -^ 



} a list ' 



Chatelier valve pipe 
from Cylinder exlu 

passage to cab 



pipe 



Fig. 115. — Baldwin Water Brake for Compound Engine. 



304 



Air-Brake Catechism 



THE BALDWIN WATER BRAKE FOR BALDWIN COMPOUNDS. 

Q. Does what has been said in general concerning the 
water brake for a simple engine also refer to the Baldwin 
Water Brake? 

A. Yes^ and with this as with the other, the holding power 




Cylinder sajjty valve %^'''^Vy 








■^ Elbow for^S^ 
into live steam 



Pig. 116. — Baldwin Water Bkake for Compound Engine. 



The Water Brake 305 



is due to the engine being run reversed^ but in full reverse 
position^ the water being used as herein explained. 

Q. Explain the cuts (Figs. 115 and 116) referring to 
the water brake for compounds. 

A. Fig. 115 is a side view of the front end and Fig. 116 
is an end view. When water is permitted to enter pipe A 
(Figs. 115 and 116) it finally reaches a a, where it enters 
the exhaust passages. D (Fig. 116) is a gate or back pres- 
sure valve, by means of which the engineer can regulate the 
amount of back pressure against which the pistons will oper- 
ate. J? is a safety valve located in the live steamways to per- 
mit any back pressure above a given amount to escape. C 
(Figs. 115 and 116) are air inlet valves, which when neces- 
sary permit air to enter the cylinders and prevent smoke and 
cinders from being drawn in. B (Fig. 115) is a hinged lid 
used to close the exhaust nozzle. 

Q. How is the brake put to work? 

A. The initial steps are the same as with the water brake 
on simple engines: open cylinder cocks^ put reverse lever in 
extreme backward position^ and open the water valve. The 
exhaust nozzle lid B should also be closed^ and the air inlet 
valves C be opened. 

Q. Trace the passage of the water or steam. 

A. As air enters the inlet valve C (Fig. 115) it mingles 
with the hot water and steam entering the exhaust cavities 
from a a. From here it passes by the piston valve G and 
enters the low pressure cylinder. When the movement of the 
piston in the low pressure cylinder is reversed this combina- 
tion of steam, water and air^ excepting that which escapes at 
the cylinder cocks, is compressed while the other end of the 
cylinder is being filled. The steam being compressed passes 
by piston G and on, as indicated (Fig. 116), into tlie oppo- 
site end of the high-pressure cylinder H. On the return 



306 Air-Brake Catechism 

stroke of the piston it is forced from the high-pressure cylin- 
der by the piston valve and on into the steam pipe J J, where 
what does not escape at the back pressure valve D accumu- 
lates. The safety valves E take care of any pressure in excess 
of a safe amount. 

Q. How is the water brake operated on a two cylinder 

compound of the Schenectady type? 

A. Generally two water pipes are used on account of the 
vast difference in the sizes of the two cylinders, and the ex- 
haust valve between the receiver and the low pressure exhaust 
passage is left closed while using the water brake. Otherwise 
the water brake is used practically the same as on a simple 



engine. 



LUBRICANTS. 



Q. What lubricants should be used in the different 
brake apparatus? 

A. Steam Cylinder of Pump — Valve Oil. 

Air Cylinder of Pump — Valve Oil. 

Brake Valve — High-grade Machine Oil. 

Triple Valve and High-speed Eeducing Valve — High- 
grade Mineral Oil in the cylinder^ and a very 
fine dry graphite on the slide valve. 

Brake Cylinder — A light grease that will not flow in 
Summer or become thick in Winter. 

AIE-BEAKE EECOEDING GAGES. 

Q. What is an air-brake recording gage? 

A. It is a mechanism by means of which lines are traced 
upon a chart. An examination of these lines will tell exact- 
ly how the brakes have been manipulated by the engineer. 

Q. What causes the lines to be traced upon the chart? 



Recording Gages 307 

A. The contrivance lias an arm containing a pen which, 
is raised or lowered as the pressure fluctuates in the place 
to which the gage is piped. As the pen and chart move^ a 
line is traced showing the variation of the pressure. 

Q. What causes the chart to move? 

A. It is connected with a clock movement, by the adjust- 
ment of which the movement of the chart is controlled. 

Q. To what else is the recording gage similar? 

A. To a steam indicator; but in that case steam instead 
of air causes the pen to rise or lower as the pressure changes, 
and the movement of the main steam piston imparts a move- 
ment to the indicator drum upon which paper is fastened, 
and upon which a line is traced by a pen or pencil. 

Q. To what part of the air-brake system is the record- 
ing gage piped? 

A. It may be piped to the brake-pipe the auxiliary re- 
servoir, or the brake cylinder. On a passenger train^ the gage 
is usually placed at the rear of the train, while on a freight 
train it is placed in the caboose. 

Q. Which of these places is preferred? 

A. The brake-pipe. So connected^ the chart shows the 
fluctuation of pressure when the brakes are applied and re- 
leased, and the exact habits of the engineer are shown. 

Q. From the record made by a recording gage, what 
may be ascertained? 

A. The amount of brake-pipe pressure carried; the cor- 
rectness of the air gage ; the method employed by the engineer 
in the application and release of the brakes; the position of 
the brake-valve handle in releasing brakes and recharging the 
train; it is a valuable adjunct in finding the cause of air- 
brake wrecks or ^^f allures'^ ; shows if the air-brake instruction 
of the road is lived up to ; shows how long it takes to recharge 
with the different main reservoirs and pumps on the different 



308 



Air-Brake Catechism 



engines; it is a valuable aid in discovering the cause of slid 
flat wheels; it increases the interest of the engineers in air- 




brake matters, as their record and skill are shown by tlie lines 
on the chart; besides these things, a great deal of kindred 
information ma}^ be gleaned by a careful study of the charts. 



Recordixg Gages 309 

Q. At what speed does this chart usually move? 

A. From two and one-quarter to four and one-half inches 
an hour^ as desired^ any choice can be met by the manufac- 
turers. The speed can be adjusted by means of the clock. 

Q. Is there any advantage gained from a slow or fast 
movement of the paper? 

A. A slow movement condenses the record and does not re- 
quire so large a chart, while a fast movement uses a larger 
charts but shows a greater corresponding amount of detail. 
If a slow movement is used, and the detail is desired at any 
particular pointy such as a water crane or milk depot^ the speed 
of the paper may be" adjusted as desired. 

In Fig. 117, the broken line shows the path the pen would 
trace if there was a constant pressure of 70 pounds. No 
pressure is represented by the circumference of the small cir- 
cle. 

The figures at the top are a time reference and the figures 
up and down refer to the amount of pressure. 

The distance between the lines running up and down repre- 
sent the time element. The chart (Fig. 117) shows two 
records on the same run made by two different men. A study 
of the two shows several points of interest. 

The best work shows on the card to the right; the card 
at the left shows that the feed valve was not adjusted properly 
for a 70 pound brake-pipe pressure, or else the gage was 
wrong; the card at the right shows three station stops where 
the engineer made more than a 20 pound brake-pipe reduction^ 
while the card at the left shows the same thing at six sta- 
tions, and at almost every station the stop was made by two 
applications of the brake. The amount of reduction points 
very strongly to the use of the emergency. 



CHAPTEK XI. 

TRAIN INSPECTION 

Q. Why is train inspection necessary? 

A. To find and remed}^, before trying to handle the train 
on a grade, any defects that would render its handling un- 
safe ; iDart of the pistons may be out against the cylinder heads 
when the brakes are applied^ the retaining valves may be poor, 
some brakes may not apply^ auxiliaries may not charge^ leaks 
may exists the brakes may go into emergency when trying to 
make a service application^ and many other defects may exist. 

Q. Where should we begin to get a train ready? 

A. At the rear. 

Q. Is it wrong to start at the head end? 

A. It would not be were the cocks not opened between 
the tender and cars. If the cocks were opened, the air would 
blow through and out of a chance open cock, and a loss of 
time and air would result. 

Q. Commencing at the rear, what should be done first? 

A. The rear angle cock must be closed and the hose hung 
up. 

Q. What harm is there in allowing the hose to drag? 

A. It collects dirt and cinders, which are blown into the 
train and help to close strainers, and which work into the 
triples and cause them to wear faster. In winter, ice getting 
into the hose may block it. 

Q. What should we do as we go towards the engine? 

A. See that the retainer handles are turned down^ hand 



Train Ixspection 311 

brakes released, hose coupled^ and cocks turned so that the 
cars are cut in. 

Q. How does the cock in the cross-over pipe, connect- 
ing the brake pipe to the triple, usually stand when the 
car is cut in? 

A. At right angles to the pipe. 

Q. How should the angle cocks stands at the end of 
the car when cut in? 

A. Parallel with the pipe. 

Q. Do the angle cocks and cut-out cocks always stand 
as just described? 

A. No ; sometimes in just the reverse positions. 

Q. Why is this? 

A. These are cocks used with very old equipment and 
may be readily recognized^ as they differ in shape from those 
now employed. If in doubt^ look at the crease in the top of 
the plug, which always stands parallel to the opening in the 
valve. 

Q. What should we always do before coupling the 
hose between the engine and cars? 

A. Blow out the brake-pipe on the engine to get rid of dirt 
and water. 

Q. After coupling the hose and turning the angle 
cocks, are we ready to look over the brakes? 

A. No^ not until the pump has charged the train. 

Q. With a constant pressure of seventy pounds in the 
brake pipe, how long should it take to charge one 
auxiliary reservoir from zero to seventy pounds with the 
modern equipment? 

A. About seventy seconds. 

Q. How long does it take to charge a train of twenty 
cars? 

A. This depends on the condition of the pump and the 



312 Air-Brake Catechism 

leaks in the train. If the capacity of the pump were sufficient 
to keep a constant brake-pipe pressure of seventy pounds, 
twenty cars could be charged as quickly as one. This can- 
not be done, as twenty feed grooves usually take air from the 
brake-pipe faster than the pump will supply it. 

Q. Who should tell when it is time for the test? 

A. The engineer. He should wait until full pressure is 
obtained and then make a twenty-pound service reduction. 

Q. What should then be done? 

A. One brakeman should go over the train turning up the 
retainer handles, while the other examines piston travel and 
looks for leaks. 

Q. What should the piston travel be? 

A. If no rule exists on your road in regard to this^ a pis- 
ton travel between 5 and 8 inches will be found to give good 
satisfaction on ordinary grades. 

Q. What should be done after the retainer handles 
are raised and the piston travel adjusted? 

A. The engineer should be signaled to release, and then 
there should be a wait of fifteen or twenty seconds, to allow 
the brake-cylinder pressure to reduce to what the retainer 
holds. 

Q. What should then be done? 

A. The man on deck should turn down the retainer han- 
dles. If a blow issues from the retainer when the handle is 
turned down, the retainer is working properly. A strict 
count of those working should be kept. The man on the 
ground should walk along and see that the brakes release when 
the retainer handles are turned down. 

Q. What should be done after the inspection is com- 
pleted? 

A. A report should be made to the engineer and conduct- 



Train Inspectiot^ 313 

or, giving them a knowledge of the piston travel, the num- 
ber of retainers in working order, the number of cars, the 
number of air cars in working order, and the tonnage and any 
general information concerning the condition of the train. 

Q. In testing, would it do for a brakeman to open the 
angle cock at the rear of the train to set the brakes? 

A. This is decidedly a poor practice; brakes that cannot 
be worked from an engine will sometimes work by opening 
an angle cock. If a hose lining were loose^ a brakeman might 
apply the brakes and an engineer release them all right, while 
in making the reduction from the engine, the brake-pipe re- 
duction going ahead might roll uj) the lining and close the 
hose. We want to know just how the brakes will work from 
the engine. 

Q. If there is a leak in the hose couplings, what should 
be done? 

A. Turn angle cocks, break the coupling, and, if the seat 
is bad and there is no extra hose gasket, make the seats round, 
if they are not so, and recouple. If the leak still exists, break 
the coupling, put a small stick back of each lug, and close 
the couplings on them* 

Q. Why should paper never be used to make a joint? 

A. It works into strainers, often causing an auxiliary-re- 
servoir to charge slowly, and it may prohibit getting quick- 
action on this car. 

Q. When inspecting a train, if we find a brake that 
does not apply with the rest, what should be done? 

A. See that the car is cut in properly, and try the drain 
cock to see that there is air in the auxiliary reservoir. If the 
auxiliary is charged, signal the engineer for a brake-pipe re- 
duction. 

Q. If the brake applies and then leaks off gradually, 



314: Aie-Brake Catechism 

without any air coming out of the triple exhaust, what is 
probably the trouble? 

A. The air is blowing by the packing leather in the brake 
cylinder. 

mJ 

Q. How can a brake that does not apply when the re- 
duction is made sometimes be made to work? 

A. By cuttinor it off from the car ahead and the one behind 
it and opening the angle cock. The cylinder may be dirty, and 
setting the brake in the emergency may loosen the dirt and 
cause it to work properly. 

Q. If the auxiliary reservoir were found to contain no 
air when the drain cock was opened, what might be the 
trouble? 

A. The feed grooves might be corroded shut in the triple ; 
the strainer where the cross-over pipe joins the main brake- 
pipe, or the one where the cross-over pipe joins the triple, 
may be filled with dirt and scale. 

Q. Is it good practice to pour oil into a hose to make 
a brake work? 

A. Decidedly not; it may occasionally furnish temporary 
relief, but it will decay the rubber-seated valve in the triple 
and dampen the strainers, pipe, and triples so that dirt will 
adhere to them and render them stickv\ 

Q. Is a small leak, one that the pump will easily over- 
come, more easily managed in a long or a short train? 

A. Tn a long train. 

Q. Why? 

A. Because there is a much larger vohmie of air in a 
long brake-pipe, and the reduction causing the brakes i 
leak on harder after being applied will be much slower on 
a long than on a short train. Frequently a leak that could 
not be gotten along with in a train of three or four cars, 
if cut in with twentv tidit cars, would not be noticed. 



Train Inspection 315 

Q. If a retainer were broken off and the pipe plugged, 
what would result? 

A. After the engineer applied the brake^ he coukl not re- 
lease it^ as the exhaust port would have been closed. 

Q. Would it interfere with applying the brake? 
A. No. 

Q. If a brake sticks, what should be done? 

A. Look to see that no retainer handle is iip, that the hand 
brake is not set^ and that no lever is caught. Then signal 
the engineer again to release. If he is unable to release it;, 
cut the car out and bleed it. 

Q. Should a car be bled when cut out? 

A. Alwaj^s; a leakage of brake-pipe pressure between ■'"be 
cut-out cock and the triple might cause the brake to appl}^ 
after it was cut out^ if any air were left in the auxiliar3^-reser- 
voir. 

Q. If the piston stays out on a car after we hear the 
air escape from the triple exhaust port, what is wrong? 

A. The release spring is probably weak or broken. 

Q. Is it necessary to cut such a brake out? 

A. No ; the jar of the wheels against the shoes will force 
the piston in. 

Q. If two hose couplings are frozen together, how 
should they be separated? 

A. The ice should be thawed^, or the gaskets will be torn. 

Q. If a triple fails to work because it is frozen, what 
should be done? 

A. It should be thawed and the drain plug removed in the 
bottom of the triple^ to remove the water and avoid a repeti- 
tion of the trouble. 

Q. What three things would cause the brakes to go 



316 Air-Brake Catechism 

into emergency when making a gradual brake-pipe re- 
duction? 

A. A weak graduating springy a l^roken graduating pm, 
and^ by far the most likely, a sticky triple. 

Q. How would we find the triple causing the trouble? 

A. On a train of five or six cars we can watch to see which 
brake grabs first and cut the car out. On a train of over 
seven cars, the brakes do not usually apply with the first re- 
duction on tlie car causing the trouble, so, to find the faulty 
triple, have the engineer make a five-pound brake-pipe re- 
duction, find the car with the brake not set and cut it out. 
Then try again with all cut in to be sure that the faulty 
triple has been found. 

Q. How would we find the faulty triple if the brakes 
went into quick action with the first reduction on a long 
train? 

A. Turn an angle cock in the middle of the train and 
see which half contains the trouble; continue in this manner 
until the trouble is located in a five car lot; have the brakes 
applied and watch these five as already described, cut out the 
defective brake. 

Q. If the emergency has been used, or we find a car 
cut out, and, when we cut it in, a strong heavy blow issues 
from the triple exhaust and at the same time the brake 
sets on the car and cannot be released, what is the 
trouble? 

A. The emergency piston is stuck down, holding the em- 
ergency valve from its seat. 

Q. How can we close it? 

A. Tap the triple lightly. If this does not work, turn 
the cut-out cock in cross-over pipe until the blow stops and 
then cut it in suddenly; the sudden flow of air may close 
the valve. 



Train Ixspectio^t 317 

Q. In trying the brakes on a passenger train, how 
should the signal be given? 

A. From the head car to apply them and from the rear 
car to release them, to be sure that the whistle-line cocks 
stand right throughout the train. On an excursion train 
the signal should be tested from ever}' car in the train. 

Q. Explain a means by which poor brakes can be de- 
tected. 

A. By feeling of the wheels at the foot of a grade. 

Q. What will characterize the wheels on the cars hav- 
ing the poor brakes? 

A. They will be cold, or cooler at least, than the others. 

Q. What is this test called? 

A. The thermal test. 

Q. Would we expect to find the same degree of heat 
in all the wheels? 

A. Xo; the heavier cars will have the greater braking 
power as compared with the lighter ones, and these cars would 
naturally have warmer wheels. This test, nevertheless, is a 
very valuable aid in detecting poor brakes. 

Q. How would you account for it if a test was made 
at the top of a grade and all the brakes applied, but some 
of the wheels were found to be cold when making the 
thermal test at the foot of the grade? 

A. One of four chief causes is generally responsible for 
this condition — low braking power, poor packing leathers, 
poor retainers, or triple feed grooves in a dirty condition. 

Q. What could dirty feed grooves have to do with 
the cool wheels if the auxiliary reservoirs charged all 
right and the brakes applied properly at the top of the 
grade? 

A. In the usual yard test air enough will leak by the 



e318 Air-Brake Catechism 

triple-piston packing ring and charge the auxiliary reser- 
voir so that the brakes will apply properly even if the feed 
groove is dirty. In descending a heavy grade there are but 
a few seconds in which to recharge between brake applica- 
tions; as a result the reservoirs on the cars are never re- 
charged after the first application that is made on the grade, 
and the brakes on these cars are^ as developed by the thermal 
test^ practically useless, although they did pass the first 
test. 

TEAIX HAXDLIXG. 

Q. What should we always do before coupling to a 
train? 

A. Start the pump and be sure that everything is work- 
ing properly. Do not wait to discover pump or engineer's 
valve defects when your train is in and ready to proceed. 

Q. How should an engineer handle the brake on his 
engine in coupling to a train? 

A. In backing onto a train^ especially an empty one^ he 
should make two or three applications of his driver and ten- 
der brakes, and leave his valve on lap when coupling to the 
train. 

Q. Why is this done? 

A. To couple to the train with reduced auxiliar}^ pres- 
sures. 

When the cocks between the engine and tender are turned, 
in coupling a train to an engine, the brakes are usually ap- 
plied on the engine and tender on account of the reduction 
caused by the air flowing back into the train. If the brake- 
pipe is long and empty, the main-reservoir pressure might flow 
back and equalize with that in the brake-pipe at so low a 
pressure that it might not be able to overcome the tank and 
driver auxiliary pressures so as to force these triples to re- 



Train HxVndlinc 319 

lease position. In this case the two brakes would be stuck, 
and if more cars were to be picked up^ we would have to wait 
to pump up, or get down and bleed these two brakes off. If 
we had backed onto the train with reduced auxiliary-reser- 
voir pressures on the engine and tender^ we would not have 
met with this trouble^ as the main-reservoir pres- 
sure could then have raised that in the brake-pipe sufficiently 
to have released the brakes. 

Q. What should be done after getting our cars placed 
in the train? 

A. We should wait until everything is fully charged. 

Q. How can we tell when the train is charged? 

A. The pump will nearly stop; or place the valve on lap^ 
and if everything is charged the black hand will not fall. 

Q. What should then be done? 

A. A thorough test of piston travel, leaks^ and retaining 
valves should be made before attempting to handle the train 
on grades. 

Q. How much reduction should be made? 

A. A gradual twenty-pound reduction. 

Q. Why is it necessary to make a test? 

A. A part of the pistons may be traveling against the 
cylinder heads^ the travel may be too shorty the retainers may 
not be good, or there may be something wrong with a triple 
that would throw the whole train into emergency when the 
service application was desired^ in which case freight might 
be shifted or broken, especially in a train partly equipped with 
air brakes. 

Q. In testing brakes, from what point should they 
always be applied and released? 

A. From the engine. 

Q. How could it happen that a brakeman could turn 



320 Air-Brake Catechism 

an angle cock at the rear of the train and apply tha 
brakes, and an engineer could release them, but that the 
engineer could not set them from the engine? 

A. The lining of a hose might be loose, so that the en- 
gineer could throw air back into the train to release the 
brakes, but when a reduction was made, the air flowing in 
the opposite direction might roll the lining up and close the 
hose. 

Q. Is this a common occurrence? 

A. No, but it is by no means unheard of. 

Q. What else should always be tested? 

A. The brake-pipe, to see if it leaks, and how much. 

Q. How should this be done? 

A. B}^ making a seven-pound reduction in service posi- 
tion and then placing the valve on lap. Watch the black 
hand, and the fall of it will show the leak in the brake-pipe. 

Q. Will not a leak in the brake pipe show if the valve 
is simply lapped without first applying the brakes? 

A. It will in time, but not nearly so quickly as by the 
other way. 

Q. Why not? 

A. If the valve is simply lapped, the brakes are not ap- 
plied, the triples are in release position, and the feed grooves 
connect the auxiliary-reservoirs and brake-pipe. If there is 
a leak in the brake-pipe with the triples in release position, 
the air from the auxiliarj^-reservoirs will leak through the 
triple feed grooves back into the brake-pipe, and not only the 
brake-pipe but the auxiliary-reservoir pressures will have to be 
reduced before the black hand on the gauge will register the 
leak. 

Q. Why is the other way quicker? 

A. If tlie brakes are first ai^plied and the valve then placed 



Train^ Handling 331 

on lap^ the feed grooves in the triples between the auxiliary- 
reservoirs and brake-pipe have been closed and the leak sim- 
ply has to reduce the brake-pipe pressure when the black hand 
will register the leak. With a large volume of air a given 
leak will reduce the pressure much more slowly than the 
same leak drawing air from a smaller volume. 

Q. Just as soon as a train tips over the summit of a 
hill, what should be done? 

A. A reduction of brake-pipe pressure should be made 
to be sure that no angle cocks have been turned and that the 
brakes take hold properly, also to get the use of the retainers 
as soon as possible. ■ 

Q. How can we tell if the angle cocks back of the tank 
are properly turned? 

A. By the sound of the brake-pipe exhaust. The more 
cars of air the greater the volume of air in the brake-pipe, 
and the longer the equalizing piston will have to stay up 
to make a given reduction. 

Q. What should be done if the brakes do not hold 
properly, or we know by the brake-pipe exhaust that an 
angle cock has been closed? 

A. Blow brakes before the train gets to moving fast. 

Q. How much reduction should be made for the first? 

A. Not less than five pounds, unless K triples are in use, 
and after we get over fifteen cars it is better to make a seven- 
pound reduction. Five pounds using K triple valves will 
apply all brakes on trains unless of exceptional length. 

Q. In a part air train, what would be the harm in 
starting with a ten-pound reduction? 

A. The brakes setting hard on the air-brake cars would 
cause the slack on the non-air cars to run up hard, causing 
a jar that would be likely to damage the car or the contents, 
to sav nothing: of the effect on the crew in the caboose. 



322 Air-Brake Catechism 

Q. Why is a light reduction, when not using K type 
of triples, liable not to set the brakes, especially on a long 
train? 

A. Because, with a large volume of brake-pipe pressure, 
reductions are made so slowly that there is a tendency for 
auxiliary-reservoir pressure to feed through the triple feed 
grooves into and equalize with that in the brake-pipe, in 
which case the triple jDistons would not move; or, if they 
did, the air going from the auxiliary-reservoir into the brake 
cylinder very slowly would blow through the leakage grooves 
past the pistons and out to the atmosphere. 

Q. How much should be made for the second reduc- 
tion? 

A. This is governed largely by circumstances, but the best 
results with long trains will be gotten if no very light reduc- 
tions are made. If the reduction is being made on a long 
train and the packing rings of some of the triples are a 
little loose, there is a tendency on the part of the auxiliary- 
reservoir pressure, that should go to the brake cylinders, to 
leak back into the brake-pipe by the packing ring. 

Q. We continue our brake-pipe reductions until finally 
our brakes are fully set, that is, all the auxiliary reser- 
voir and brake-cylinder pressures have equalized. How 
much reduction is usually necessary to accomplish this, if 
the piston travel is not over 8 inches? 

A. About twenty pounds, if it is made with one reduc- 
tion ; but in handling a train on a grade, if we needed to get 
all we could, it would be permissible to make a twenty-five- 
pound reduction. With K triples 17 and 22 pounds reduc- 
tions are sufficient. 

Q. Give the reason for this last statement. 

A. In descending a grade, we may liave gone one, two, 
or three miles, while we have been making g, twenty- 



Train Handling 323 

pound reduction. Naturally, some of the air put into the 
brake cylinders lias escaped by the packing leathers to the 
atmosphere in going this distance^ and making another brake- 
pipe reduction will let more auxiliary-reservoir pressure to 
the cylinders. Where the twenty-pound reduction was made 
with one reduction/the air had no time to leak away by tlie 
cylinder packing leathers. 

Q. Suppose we had already made a twenty-five-pound 
reduction and the packing leathers in the brake cylinders 
were practically tight, if we continued taking air from 
the brake pipe, would the brakes be set any harder? 

A. No. 

Q. Would we lose any braking power? 

A. Yes. 

Q. How would we lose braking power? 

A. The brake is already fully set^ that is, the auxiliary- 
reservoir and brake-cylinder pressures are equal; with a fur- 
ther reduction of brake-pipe pressure, no more auxiliarj^-res- 
ervoir pressure can go to the cjdinder ; but just as soon as the 
auxiliary-reservoir pressure is enough greater than that in the 
brake-pipe to overcome the resistance of the graduating spring 
in the triple, the triple piston will be forced to emergency 
position, and we will have a direct connection between the 
auxiliary-reservoir and brake cylinder through the emergenc}^ 
port in the end of the slide valve. The brake-pipe pressure 
being less than that in the auxiliary-reservoir and cylinder^ 
both these pressures will begin leaking by the packing ring 
of the triple piston into the brake-pipe. 

Q. Is there any other way in which we would lose 
braking power by too heavy a brake-pipe reduction? 

A. Yes; the brake-pipe check in the emergency part of 
the Westinghouse triple is seldom air-tight, owing to cor- 
rosion. When the brake-pipe pressure is less than that in 



324 Air-Brake Catechism 

the brake cylinder^ the brake-cylinder pressure forces the rub- 
ber-seated valve from its seat and leaks by the brake-pipe 
check into the brake-pipe. 

Q. Is there usually any warning to let the engineer 
know he has made too heavy a reduction? 

A. Yes; especially on a long train^ where there are more 
packing rings to leak. 

Q. What is it? 

A. Under these circumstances^ a blow at the exhaust at 
the brake valve results. 

Q. What causes this exhaust? 

A. The engineer reduced the equalizing-reservoir pressure 
in order to cause the equalizing piston to reduce the brake- 
pipe pressure. It closed the exhaust when the brake-pipe 
was a trifle less than the equalizing-reservoir pressure. When 
too heavy a brake-pipe reduction had been made, we saw that 
the auxiliar3^-reservoir and brake-cylinder pressures fed back 
into the brake-pipe. The brake-pipe now being greater than 
the equalizing-reservoir pressure^ the equalizing piston is 
moved from its seat, and the blow at the brake-pipe exhaust 
continues as long as air is feeding into the brake-pipe from the 
auxiliary-reservoirb and brake cylinders. 

Q. Does the equalizing piston always move and give 
this warning? 

A. Xo; if there is leakage by the equalizing piston, the 
air feeds by and equalizes the equalizing-reservoir and brake- 
pipe pressures, but the braking power is lost just the same. 

Q. Is the triple piston supposed to form a joint on the 
leather gasket between the triple head and the main body 
of the triple? 

A. Yes, when tlie gasket is new, but the gasket dries out 
so that the surface is not smooth. 



Traix Handliistg 325 

Q. What places should we pick out, if possible, in 
which to recharge? 

A. Where the grade lets up a little and on curves where a 
train binds. 

Q. To release brakes, where should the handle of the 
engineer's valve be placed? 

A. In full release position. 

Q. How long should it be left here? 

A. This is governed entirely by the length of the train. 
If, in descending a grade, both hands on the gage shows that 
the brake-pipe and ,main-reservoir pressures equalize below 
seventy pounds, the valve should be left in this position until 
both hands start to go above seventy. If the pressures equalize 
about seventy pounds when the valve is thrown to full re- 
lease and stay there, the valve should be moved to running 
position as soon as the brakes are released, so as not to over- 
charge the auxiliary-reservoirs. 

Q. Why, on a long train, should the valve be left in 
full release position until both hands start above seventy 
pounds? 

A. A large port connects the main reservoir and brake- 
pipe in this position and a small one in running position, 
and we get the benefit of the excess pressure from the main 
reservoir in recharging; the pump works faster, and we can 
charge the train much more quickly, because the brake-pipe 
pressure being higher forces air into the auxiliaries faster. 

Brakes are likely to stick and wheels slide, especially on a 
long train, if we try to release brakes in running position. 

Q. Why does the pump work faster? 

A. Because there is less main-reservoir pressure for it to 
work against. 

Q. Why do the last three or four pounds feed more 



326 Air-Bkake Catechism 

slowly into the brake pipe, if the valve is put in running 
position? 

A. Because when^ in running position^ the brake-pipe pres- 
sure is almost up to tliat at wliich the feed valve is adjusted^ 
the spring in the feed valve begins to be compressed and al- 
low the little regulating valve to partly close, in which case 
the pump will compress air faster than it can get through 
the feed valve. When the main reservoir is charged to ninety 
pounds, the pump practically stops, and this is likely to hap- 
pen before the auxiliary-reservoirs are fully recharged. 

Q. Why will some brakes stick in trying to release 
them in running position? 

A. Because the brake-pipe pressure rising slowly may 
feed by some triple piston-packing rings, and allow auxiliary- 
reservoir pressure to keep equal with that in the brake-pipe. 

Q. Why may the wheels slide in this case? 

A. Because the brake on this car has been left fully set and 
the auxiliary-reservoir fully recharged. A five-pound reduc- 
tion will probably set this brake in full with a pressure of 
sixty-five pounds, and this is more than is safe, especially 
with a light car. If a brake once sticks it is very likely 
to remain stuck, as the auxiliary-reservoir and brake-cylinder 
pressures equalize so high that it requires a higher brake-pipe 
pressure to release this brake, and the brake-pipe pressure in- 
creasing slowly, gives the air a better chance to leak by the 
triple-piston packing ring. A brake acting this way may be 
all right if handled properly. 

Q. In descending a grade after getting the use of the 
retainer and having everything recharged, why is a five- 
pound reduction much more effectual than a five-pound 
reduction made without the use of the retainer? 

A. Because in one case we are putting five pounds from 
the auxiliary reservoir into fifteen pounds in the cylinder^ 



T^Aix Handling 327 

and in the other we are putting five pounds from the auxiliary 

reservoir into an empty cylinder^ and a part of that put in 

blows through the leakage groove before the piston travels far 

enough to close it. 

Q. If a twenty-pound brake-pipe reduction will apply 

a brake in full without the use of the retainer, how much 

reduction ought to set brakes in full after getting its use? 
A. Not over fifteen pounds. 

Q. If all retainers are being used, is it necessary after 
charging up to make a five or seven pound for our first 
reduction? 

A. Yes^ with old equipment, some of the retainers might 
have been out of order, so as not to hold any air in the cylin- 
der^ and less than a five-pound reduction would not catch 
these brakes again. 

Q. What should an engineer do, if, when he is not 
using the brakes, he feels them applying so as perceptibly 
to diminish the speed of the train? 

A. He should place the handle of the engineer's valve 
on lap. 

Q. Why? 

A. Probably a hose has burst, or the conductor is using 
the conductor's valve. If the valve is not lapped, the main- 
reservoir pressure will be lost^ and there will be no pressure 
with which to release the brakes and recharge the auxiliaries. 

Q. Which is less dangerous, a leak that will gradually 
slow a train up, or one that will simply keep the train 
running steadily? 

A. A leak that will slow a train up is much to be preferred. 

Q. Why? 

A. If the leak simply runs the train steadily and the 
engineer allows the pressure to gradually leak away because 
he seems to be making a nice, even run^ he would have a dif- 



328 Air-Beake Catechism 

ficult time stopping the train if necessity demanded it, after 
the pressure liad leaked down to fifty pounds. 

Q. Should an engineer try to make as uniform a run 
with air as can be done with hand brakes? 

A. As a rule, no. although on some light grades a few re- 
tainers will run them smoothly. On heavy grades and long 
trains it is necessary to slow up to recharge. It will be 
found that a much more uniform run can be made with K 
triple valves, as lighter reductions result in a more positive 
response and a higher cylinder pressure is developed for a 
given reduction, hence it will not take so long to recharge, 
and the speed can be maintained more uniform. 

Q. What should always be done, where possible, in 
making brake-pipe reductions? 

A. Watch the gage. 

Q. How do you account for the fact that sometimes, 
after a seven-pound reduction of equalizing reservoir pres- 
sure is made and the valve lapped, the gage records only 
a five-pound reduction when the brake-pipe exhaust 
closes? 

A. The equalizing piston has allowed brake-pipe pressure 
to feed by it into the equalizing reservoir. 

Q. Is this more likely to happen on a long or a short 
train? 

A. On a long train. 

Q. Why? 

A. As there is a greater volume of air in the brake pipe 
of a long train, it takes longer to reduce the pressure, and the 
])rake-pipe pressure has a longer time to leak in the manner 
described. 

Q. If a quick reduction is made in emergency with the 
engine alone, and the valve is then placed on lap, why is 



Traix Haxdlikg 329 

the tank or driver brake likely to kick off, although they 
would stay set in service application? 

A. In emergency position^ air is drawn directly from the 
brake pipe without taking any from the equalizing reservoir. 
When the valve is placed on lap, the equalizing-reservoir pres- 
sure leaks by the packing ring of the equalizing piston, raises 
the brake-pipe pressure, and kicks off one or both brakes. 

Q. Why will this happen on an engine and not on a 
train? 

A. The volume of air in the brake pipe of an engine 
alone is very small, and a slight leak into it is sufficient to 
raise the brake-pipe • pressure and release the brake. With 
a train, the brake-pipe volume is so large that the leakage 
into it from the equalizing reservoir is not sufficient to affect 
the triples. 

Q. The release of the brakes on the engine alone, after 
the use of the emergency, is ascribed by some to the surge 
of air. Is this the cause? 

A. ISi'o; a surge of air would release the brake almost in- 
stantly. The brake does not release sometimes until five or 
ten seconds have passed. 

Q. Why will this happen on one engine and not on an- 
other? 

A. This simply means that on one the triple piston-pack- 
ing rings are looser than that in the equalizing piston, and 
the brake-pipe pressure feeds by the triple piston and equal- 
izes with that in the auxiliaries. A variation in the fit of the 
equalizing-piston packing rings on the different engines would 
also account for this. 

Q. The above usually happens when stopping an en- 
gine at a water-crane or on a turntable. How are these 
stops best made with the air? 

A. One application is best to use with an engine alone. 



330 Air-Brake Catkchism 

If we find that we are stopping three or four feet shorty 
open the throttle, and the engine can be helped along a short 
distance and a smoother stop be made. 

Q. What happens every time you use the emergency 
on a turntable? 

A. You strike the table a blow which is the result of the 
weight and the speed of the engine, and then^ if the turn- 
table breaks down, wonder why the company does not pro- 
vide a decent table. 

Q. In making a water-tank stop with a passenger train, 
how should it be done to avoid a jar to the train and pas- 
sengers? 

A. The stop should be made with two applications of the 
brake, when using the old equipment, unless the grade is too 
steep and the pressure too low for safety. With the gradu- 
ated release triple the brake is set with a high pressure, and 
this pressure is graduated off as the stop is approached. It 
may be necessary to make another reduction ; if so, the re- 
sponse is quick as the shoes are already against the wheels, 
there is pressure in the cylinder and the L triple contains the 
quick-service feature. 

Q. How do we handle the valve to make the first re- 
lease so that the brakes will respond with the first reduc- 
tion when using old equipment? 

A. When the speed of the train has been reduced to that 
desired, throw the valve handle to full release and bring it 
back on lap immediately. 

Q. Why bring it back on lap? 

A. So as not to raise the brake-pipe pressure too high. 
The feed grooves in the triples are small, and have only 
three or four seconds in which to equalize the brake-pipe and 
auxiliary-reservoir pressures. If the valve is left in full 
release or running position, and the brake-pipe pressure gets 



Train Handling 331 

to seventy pounds^ and there is^ say, only fifty-iive pounds 
in the auxiliary reservoirs^ the triple pistons will not move 
to service position until over a fifteen-pound reduction of 
brake-pipe pressure has been made. By the time we have 
made this amount of reduction in service position we shall 
have gone by the water-crane^ unless we use the emergency, and 
that is what is usually done if the engineer is not up to date. 

Q. When should brakes be released on a passenger 
train? 

A. Just before the train stops. 

Q. What should be done on a grade just heavy enough 
so that the train will start with the brakes released or 
with a train of more than ten cars. 

A. Stop the same as at a water-crane. No jar will be 
felt with a light application. With the L triple valve the 
pressure may be graduated down to that just sufficient to 
cause the train to remain at rest. 

Q. How about a heavy grade? 

A. Our stop, if we do not have the graduated release 
feature, will then depend on the grade and our pressure. 
Safety should be of first importance, even if the stop is a 
trifle rough. 

Q. What makes the jar, if the brakes are not released 
before the train stops? 

A. With the brakes set hard, the trucks are distorted, 
and it is the struggle of the trucks to right themselves that 
causes the jar. 

Q. Can brakes be started releasing longer before 
stopping after a light or a heavy reduction? 

A. After a heavy reduction, as there is more air in the 
cylinders to be gotten rid of;, and the brakes release more 
slowly. 



332 Air-Brake Catkchtsm 

Q. What is meant by an application? 

A. It covers all the time i'roiii the moment the brake is 
applied until it is released; three or four reductions may be 
made during one application. 

Q. In making a stop with a freight train, when should 
brakes be released? 

A. After the train comes to a full stop, to avoid breaking 
tlie train in two if the slack runs out hard in releasing before 
stopping. 

Q. If we have stopped short with a freight train, and 
need to release before stopping to pull up farther, what 
should be done? 

A. We should wait for the slack to adjust itself in the 
train before using steam. Even then the steam should be 
used very cautiously. 

Q. In running passenger trains over cross-overs to get 
around freights, what care should be taken? 

A. To do this, brakes have to be used when flagged, at 
the upper cross-over, lower cross-over, and usually at a 
station. We should charge up as much as possible after 
each application. Do not follow the plan of releasing and 
putting the valve on lap in such a case to be sure the triples 
will respond quickly, '^'hey will respond quickly, but if the 
station stoj) is on a grade, you may not have air enough left 
to make it when you get there. 

Q. What is the usual cause of trains running away? 

A. Making a great many reductions witliout occasionally 
charging up ; or allowing the pressure to leak away, because 
the train is nmning steady, and then wlien we get ready to 
recliarge, not liaving enough air hi'i to slow u|) the train; 
l)y not stopping to recharge when aii* is gradually being lost 
and l)y maintaining too high a speed when the brakes arc not 
holding well. 



Tratx Haxdltn-g 833 

Q. On a fast passenger run. how may time be saved in 
using the brake? 

A. By waiting longer before applying the brakes and then 
making a ten-pound reduction at the start. 

Q. Will this not jar the passengers? 

A. Xot when going fast. Passenger trains are continu- 
ous, and there is very little slack to run up. A ten-pound 
reduction made with a train moving ten miles an hour would 
produce a very unpleasant sensation to passengers, where at 
forty miles an hour it would not be noticed. This is explained 
under the subject Old-Style High-Speed Brake. 

Q. Should brakes be tested in taking on cars? 

A. Yes, to be sure that tlie brakes on these cars work 
properly, and that the brakes back of them can be applied 
and released through them. 

Q. When all retainers on a train are not necessary, 
how should they be used? 

A. At the head end if the grade is short; otherwise 
change them around and use them on every other car, so as 
not to overheat any wheels. 

Q. If the brakes are applied and the engineer wishes 
to release and drift two or three hundred feet before 
stopping, what should be done? 

A. Enough retainers should be left in operation to keep 
the slack bunched. This, of course, is not usually necessary, 
if the engine is equipped with an independent brake. 

Q. When should hand brakes be used? 

A. On tlie rear of a part air train when backing it into 
a siding; if it stands on a knoll, to keep the slack from running 
back; to aid the air when the brakes are not liolding well. 

Q. Should hand brakes and air brakes be used together 
on the same car? 



334 Air-Brake Catechism 

A. This is a risky practice. If the two brakes work to- 
gether, we are very likely to heat or slide wheels; if they 
work in opposition, there is danger of a brakeman being 
thrown from the car; and the hand brake being applied will 
take up the slack in the brake rigging, so that the piston 
cannot get by the leakage groove. 

Q. If hand brakes be used back of the air, if there are 
not enough air brakes to control the train, what is likely 
to happen? 

A. This is likely to produce a bad effect when the air 
brakes are released. If the retainers are poor and allow 
the slack to run out, the train may be broken in two. 

Q. If hand brakes are to be used with the air, where 
should they be applied? 
A. Xext to the air. 

Q. Should driver brakes be cut in when descending a 
heavy grade? 

A. Always, or so much more work is thrown on the car 
brakes. The use of a water brake would, of course, be an 
exception to this rule. 

Q. If cut in all the time on heavy grades, would the 
tires not become overheated? 

A. In heavy grade work the piping is usually so arranged 
that a cock can be closed between the triple valve and brake 
cylinder, or a pipe from the brake cylinder is run into the 
cab and a cock attached to same. In either case the proper 
manipulation of these valves will prevent overheating of 
tires. 

Q. If an air-brake train should be stalled on a grade, 
should part of the train be left with air brakes to hold 
them until the engine comes back? 

A. Xo; the air brakes should be released one at a time. 



Train Handling 3«35 

and the hand brakes applied. If left with the air holding 
tliem^ the air might leak off and allow the train to run away. 

Q. When brakes are fully set, the long travel brakes 
are easier to release. They may be released and leave the 
short travel brakes applied. Is this good practice in hold- 
ing trains? 

A. Xo; it is very bad practice. A train may be broken 
in two in this way. 

Q. If brakes stick and will not release by placing the 
valve in full release, what should be done? 

A. Make a full service reduction and then, with a full 
excess pressure, throw to full release. If a release from the 
engine is possible^ this will accomplish it. 

Q. The practice is sometimes followed of using hand 
brakes on some of the air cars to take the place of the re- 
taining valve. If this is done, how and when should the 
hand brakes be applied? 

A. They should be applied so as to hold as nearly as 
possible what the retaining would accomplish when retaining 
the proper pressure. If the brakes work ^'^together/^ and 
the hand brake is applied when a high cylinder pressure 
exists the wheels on cars where the hand brakes are used will 
be called upon to do too much work and undue heating will 
result. Do not use hand brakes in such a case if the brakes 
work ^^^opposite.^^ 

Q. What harm is there in pulling hose apart instead of 
uncoupling them? 

A. The couplings are likely to be sprung so that they 
cannot be coupled again, and the brake pipe is likely to be 
torn from the car or engine. 

Q. Does it do any harm to lean on the rotary handle 
when the brakes are applied? 

A. Yes; if the dovetail piece that fits into the rotary is 



33(> AiR-BiiAKE Catechism 

tight on account of dirt and gum, the rotary may be cocked 
so as to allow main-reservoir pressure to feed into the brake 
pipe under the rotary and release some of the brakes. 

Q. What is the trouble, when there is a leak in the 
brake pipe, if the engine is alone, but coupled to tight 
cars, the leak does not show? 

A. The leak is in the angle cock at the rear of the tender. 
When coupled to a train, the leak is not noticed as the cock 
is open. With the engine alone the cock leaking allows air 
to pass out of the hose to the atmosphere. 

Q. In double heading, which engine should handle the 
brakes? 

A. The lead engine. 

Q. What should the second engineer do? 

A. Turn the cut-out cock under his valve and under 
no circumstance, unless in case of accident or when told to, 
should he cut in and interfere with the work of the lead 
engine. 

Q. If the pusher engine has no cut-out cock, what 
should be done? 

A. The valve should be placed on lap. 

Q. In this case, why does the equalizing piston some- 
times rise? 

A. Because the lead engineer increases brake-pipe pres- 
sure to release the brakes, and the increased pressure forces 
the equalizing piston from its seat. 

Q. How may it be seated? 
A. By putting the handle in full release position long 
enough to charge the equalizing reservoir. 

Q. In case of emergency, when it is necessary for us| 
to leave the engine, what should be done? 

A. Place the engineer's valve in emergency position and 



Train Haxdlixg 337 

leave it there. In our hurry, if we tried to lap the valve, 
we might get it into running position and release the brakes. 
Q. Why ought we never to bring our valve back from 
emergency position too quickly? 

A. There might be two or three ears cut out, a couple 
of plain triples, a contracted passage, or a couple of cars 
that would not go into quick-action on account of dirty 
strainers. If these cars were together, they would not help 
to carry the quick-action back. Generally a quick-action 
triple will not send a quick reduction through five cars which 
are cut out. In this case, if the engineer's valve had been 
lapped too quickly, the surge of air ahead from the rear end 
would release the head brakes, and all we would have would 
be a very light service reduction on the cars back of those 
cut out. If we leave the engineer's valve in emergency posi- 
tion long enough, we could at least get the full service ap- 
plication on these cars, and the emergency on those ahead 
of the cars cut out* 

Q. Should the engine be reversed when the driver 
brakes are applied, if we wish to stop quickly? 

A. No; the following test, made by Mr. Thomas, Assist- 
ant General Manager of the X., C. and St. L., clearly demon- 
strates that the air brake used alone is better than the brakes 
with the reverse lever, or than the reverse lever alone. 

The result of these tests was published in the ^95 Air^ 
Brake Proceedings, and is given on pages 264 and 265. 

The conditions of the test were as follows: 

Driving brake power, seventy per cent.; tender, one hun- 
dred per cent. ; N., C. & St. L. coaches, ninety per cent. ; 
Pullman sleeper, forty to one hundred and one per cent. 

Boyer speed recorder was used and tests were made: first, 
brakes applied; second, engine reversed; third, sand lever 
opened. Track was level, in best possible condition, and all 
circumstances favorable. 



338 Air-Brake Catechism 

From the record of tests the following valuable informa- 
tion was derived: 

First. Best stops are made with braking power not quite 
strong enough to skid wheels. 

Second. Length of stop is the same in reversing the engine 
whether cylinder cocks are open or closed. 

Third. The wheels did not lock rigidly when the engine 
was reversed without the brakes being used. 

Fourth. The tests demonstrated that the brakes used alone 
are better than with the engine being reversed. The stop is 
quicker^ and there are no flat spots obtained. 

Fifth. Enough sand is much better than too much. 

Sixth. Sand should be used before wheels start skidding, 
as its use will not start the wheels revolving when once 
skidding; it will simply increase the flat spots. 

Seventh. Sand being used on a straight track, the drivers 
did not lock when the engine was reversed, but on a curve 
they would. On a curve the engine rocks, and sand is not 
so likely to strike the rail. 

Eighth. In expected emergencies, the drivers did not lock 
when sand was used before brakes were applied and engine 
reversed, but it took so long to get the sand running first that, 
in the end, the stop was not made as quickly as with un- 
expected emergencies where the engine was not reversed. 

Ninth. The unexpected emergencies are the ones that bear 
the most weight, as expected emergencies are practically un- 
heard of. 

The table on page 339 will be of interest, as it shows how 
old and new air-brake trains can be stopped when fitted with 
air-brake trains can l)e stopped when fitted with the old and 
new Westinghouse quick-action freight brake. 

The train consisted of eighty Southern Pacific oil-tank 
cars. 



Brake-pipe 
Reduction 


Triple V 
Used 


5 lbs. 


H 


5 lbs. 


K 


10 lbs. 


H 


10 lbs. 


K 


15 lbs. 


H 


15 lbs. 


K 


20 lbs. 


H 


20 lbs. 


K 



2,275 


4,140 


S75 


1,700 


890 


1,890 


595 


1,090 


860 


1525 


-580 


1,040 


940 


1,725 


580 


1,060 



Train Handling 339 

COMPARISON OF THE NEW (TYPE K) WITH THE 
OLD (TYPE H) FREIGHT BRAKE EQUIP- 
MENTS IN ORDINviRY SERVICE 
OPERATION ON 80-CAR TRAIN, 

Triple Valve Approximate Lenghtof Stop in ft. from speed of: 
" • lOM. F.H. 20M.P.H. 30M.P.H. 

860 

330 

325 

215 

295 

220 

365 

215 

Note: The above results were obtained during the South- 
ern Pacific Brake Tests at Bassett, Cal.;, in July, 1908, with an 
80-car train of empty oil-tank cars, having 10-inch freight 
equipment and an average standing piston travel of 6.78 
inches ; brake-pipe pressure 80 pounds. Eoad bed practically 
level. 

The results are only comparative and must not be taken 
to cover all conditions. It will be noted that in some cases 
the stops are slightly longer for 20-pound reductions than for 
10 or 15-pound. This is due to the fact that in some cases 
the train came to a stop before the reduction was completed. 

PIPING. 

Q. What should be done in preparing pipe for use? 

A. After bending the pipe it should be blown out with 
steam to get rid of scale and dirt. If there is no steam at 
hand, air should be used. Under no consideration should pipe 
be used without first being cleaned. All fins should be care- 
fully removed to prevent their working loose and clogging 
strainers. 



340 



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4:2 Air-Brake Catechism 



Q. What should be done to the pipe while it is being 
blown out? 

A. It should be tapped lightly to loosen the scale. 
Q. What size pipe should be used in the different parts 
of the system? 

A. The sizes given in the air-brake catalogs are correct 
and should be strictly adhered to. 

Q. When using asphaltum or Japan varnish on pipe, 
how should it be applied? 

A. Always on the outside of the thread to be screwed in, 
as in this way it will not get inside the pipe. 

Q. In applying piping, what should be avoided? 

A, Xo sags should be allowed in which water might col- 
lect; where practicable, gentle bends should be substituted 
for elbows, and very short bends should be avoided. 

Q. Why are elbows or short bends undesirable? 

A. The friction caused by them retards the flow of air 
when a sudden reduction is desired in emergency. 

Q. Could pipe work be so crooked and elbows so 
numerous on an engine that a sufficiently quick reduction 
to cause emergency would not go through an engine? 

A. Yes ; this has been found so on engines, but the 
trouble was remedied when the number of elbows and bends 
was reduced. 

Q. How should pipe work be secured? 

A. By clamps that will hold the pipe rigidly in place so 
as not to allow the pipes to be moved, holes to be chafed 
in them, or any vibration to exist. 

Q. After the pipe work is applied, what should be 
done? 

A. It should be tlioroughly tested under full pressure, 
aud the leaks detected by the use of soapsuds. 



Piping 343 

Q. After the pipe is tested, what should be done? 

A. It should be painted with a rust-proof paint and one, 
if possible, that will not be affected by salt water dripping 
from refrigerator cars or by the acid in soft coal. 

Q. Why is larg'er pipe used on freight than on pas- 
senger cars? 

A. Because on a long freight train a sudden reduction 
will travel through the large pipe more quickly, as the larger 
the pipe the less the friction exerted to the passage of the air. 

Q. Is there any other reason? 

A. Yes; in emergency, with quick-action triples air from 
the brake pipe is put into the brake cylinder; a freight car 
being shorter than a passenger car, the larger pipe makes the 
volume of air in the brake pipe more nearly equal to that in 
the smaller pipe used on the longer passenger cars. 



CHAPTER XII. 

A FEW PRACTICAL FORMUL/E AND RULES 
FOR AIR-BRAKE INSPECTORS 



Braking }X)wer 

i 1 ) . , ,- . \ — = Total leverage. 

^ ' Lvlinder value ° 



(2) 



(3) 



l-inch piston travel :Shoe movement for 1 inch of 

^Total le^age~ "^piston travel. 

Shoe wear Total increase of piston travel to 

Shoe movement ^^^^r out a set of shoes. 

for 1 inch of 
piston travel 

Illustration of the Above Formulae. 



Assume : 

AVeight of car=40^000 pounds; it is to be braked at eighty 
]>er cent of its weight; lU-inch cylinder used; shoes l^A 
inches thick. 

Eighty per cent of 40,000=32,000 pounds. The cylinder 
value, or push on the piston, of a 10-inch cylinder, when the 
brake is set in full service, is 4,000 pounds. 

Substituting values in the equations : 

32,000 
S is the total leverage; that is, the push of 4,000 pounds 



Formulae and Eules 345 

on the piston niui^rt be multiplied 8 times to give the proper 
braking power. 

1" 

(2) — =.135"ori/8 

% of an inch is the distance that the brake shoes will 
move for each inch that the piston travels. 

11/2 1.5 

12 inches is the distance the piston travel would have to 
increase to wear out a set of shoes IV2 inches thick. 

To find the area of piston : 

Multiply the diameter of the piston iy itself, and this 

product by the decimal .7854. 

Example : 

What is the area of an 8-inch piston? 

8" X 8 = 64 sq. in. 
64 sq. in. X .7854 = 50.26 sq. in. 

50.26 square inches is the area of the piston; that is, the 
number of square inches in a circle 8 inches in diameter, 

To find the volume or cubical contents of a cylinder: 

Multiply the diameter of the cylinder by itself, this product 

by the decimal .7854, and this product by the length of the 

cylinder. 

Example : 

What is the volume of a cylinder 8 inches in diameter 
and one foot long? 

8" X 8 = 64 sq. in. 

64 sq. in. X .7854 = 50.26 sq. in. 

50.26 sq. in. X 12 = 603.12 cu. in. 

To find the pressure at which an auxiliary reservoir 
and brake cylinder will equalize with a full service ap- 
plication of the brake using an initial pressure of seventy 
pounds in the brake-pipe and auxiliary reservoir ; 



346 Air-Bkake Catechism 

Multiplij the capacitij of the auxiliary reservoir in cubic 
inches by eighty-five pounds {seventy pounds bmke-pipe 
pressure plus fifteen pounds atmospheric pressure, and di- 
vide the product by the combined capacity of the auxiliary 
reservoir and brake cylinder. The quotient will be, approxi- 
mately, the pressure plus fifteen pounds atmospheric pres- 
sure. This is not absolutely correct, as it does not take into 
account the clearance in the cylinder back of the piston with 
the brake released. This usually corresponds to about 1 
inch of piston travel. 

Example : 

Capacity of freight auxiliary reservoir = 1625 cu. in. 

Capacity of 8-inch brake cylinder with 8-inch piston 
travel = 400 cu. in. 

1625 X S5 = 138,125. 138,125 -^ (1625 + 400) = 68 
QS lbs. — 15 = 53 lbs. 

Fifty-three pounds is the pressure obtained in the auxil- 
iary and brake cylinder with the brake fully set in service. 

The formulae given below will be found convenient 
with which to find either the proper width of a lever to 
withstand a given strain, or to ascertain the fibre strain 
on a lever. 

E = Fibre strain. 

/ = distance from point power is applied to center of pin 
at point for which dimension or amount of fibre strain is 
desired. 

b = Thickness of lever. 
d = Width of lever. 

Xo allowance is made for the metal taken out of the 
lever for the pin holes, as the removal of metal has no prac- 
tical weakening effect, same being so close to the central 
axis. 

In general raih'oad air-brake practice, from 18,000 to 
20^000 is considered a safe fibre ^^train. 



Formulae and Rules 347 

6 PI 
B 



h d' 



4 



w 

Example : 

To find the fibre strain at the middle hole of a lever 24 
inches between the push-rod and outside holes^ middle hole 
12 inches from push-rod hole, width of lever 4.336 inches 
at middle hole, lever 1 inch thick, 10-inch cylinder used, 
and a maximum pressure of 60 pounds obtained in the cylin- 
der, giving a total power of about 4,700 pounds acting on 
the piston. 

6 PI 6 X 4700 X 12 

^ ^^ y^ ^ = 1 X 4.336 X 4.336 '' "" = '''''' P^^^*^^' 

Example : 

Under the same conditions as the preceding example find 
the proper width of the lever at the middle hole, permitting 
of a maximum fibre strain of 18,000 pounds. 

16 PI I 6 X 4700 X 12 

d = >J OT d= ^ or 

^B d ^ 18,000 X 1 

^=V18.8 or 6^ = 4.336 inches. 

Width of lever should be 4.336 inches. 
To reduce stops at different speeds to an equivalent 
stop at the same speeds, all other conditions being equal. 

Rule: Multiply the Icnown distance hy the square of the 
speed for which proportionate distance is desired, and di- 
vide the product hy the square of the speed at which Icnown 
stop was made. 

This rule is only practical with speeds which are not 



348 Air-Bkake Catechlsm 

more than three miles alx)ve or below the 8i)eed for whidi 
proportionate stop is to be calculated. 

Example : 

If a stop at bS miles per hour is made in 1,600 feet, and 
one at 62 miles per hour in 1,800 feet, in what distance 
would each of these stops have been made at a speed of 60 
miles per hour? 

Square of 58 miles = 3364 

Square of 62 miles = 3844 

Square of 60 miles = 3630 

1600 X 3600 

■ = i:i2 

3364 

1800 X 3600 



3844 



= 1691 



In the first case the stop at 60 miles per hcnir would have 
been made in 1,712 feet, while in the latter in would have 
taken 1,691 feet. 







Pig. 11 



N Opposite Directions. 



coMtKtcroR^ vALve- 




XENT> 



Fig. 1 



CruNO£R 

NG IN Same Direction. 



^LOHJM 



CHAPTER XIII. 

THE "PC" PASSENGER BRAKE EQUIPMENT 

Q. What does the designation ''PC signify? 

A. The Westinghouse Improved Brake Equipment 
Schedule ^TC/^ which uses a Control Valve in place of a 
triple valve. 'T^' signifies passenger, and ''C^' stands for 
control valve, 

Q. Where is it used? 

A. On heavy passenger equipment cars, weighing from 
125,000 to 150,000 or more pounds. • 

Q. Why is it necessary? 

A. The braking force required to control such heavy 
cars as effectively as the old equipments on lighter cars 
became so great as to exceed the capacity of the largest 
practicable single brake cylinder combined with the highest 
practicable leverage. ' 

Q. Was increased weight the only reason for bring- 
ing out the new equipment? 

A. No. Increased schedule speeds in the service for 
which these heavy cars are usually required; the necessity 
of economizing time in making stops so as to meet the fast 
schedules; much longer trains with very large volume of 
air to be handled; these have all imposed conditions which 
the older type of equipment cannot satisfactorily meet. 

Q. Does the ''PC equipment have all the features of 
the older passenger types? 

A. Yes, and several novel features as well. 

Q. What novel features are included as compared 
with the old high-speed brake (Schedule PM)? 

349 




Passenger Brake Equipment. Cylinders Pointing in Opposite Directions. 




FiQ. 119. PC Passenger Br.vke Equipment. Cylinders Pointing in Same Direction. 



350 Air-Brake ( ateohism 

A. 1. Graduated release and quick recharge^ same as ob- 
tained with the LN equipment. 

2. Certainty and uniformity of service action. 

3. Quick rise in hrake-cylinder pressure, 

4. Uniformity and maintenance of service hrake- 
cylinder pressure in spite of unequal piston travel or brake- 
cylinder leakage. 

5. Fixed limit in service braking power, 

6. Full emergency braking power obtainable at any 
time regardless of any service applications just previously 
made. 

7. Full emergency application automatically made 
whenever brake-pipe pressure falls to a certain point. 

8. The service and emergency features are separated 
to eliminate undesired quick action as much as possible. 

9. A low total-leverage ratio, to increase the efficiency 
of transmitting the braking force from C3dinder to brake 
shoes. 

10. Not sensitive to slight fluctuations of brake-pipe 
pressure preventing brakes from ^^creeping on'^ or causing 
undesired light applications. 

11. Quick rise inbrake-pipe pressure during release, 
to make certain that all brakes will release when desired. 

12. Greatly increased sensitiveness to release, to pre- 
vent ''stuck'' brakes. 

13. Graduated release may be eliminated and changed 
to direct release like the old equipments whenever desired 
without any change in the mechanism. 

Q. With all these new features, how does this equip- 
ment operate when mixed with old equipments in the 
same train? 

A. When the brake valve is properly handled, it works 
in perfect harmony with the old equipments, and even im- 
proves the operation of the latter. 



The '^PC^' Brake Equipment 351 

Q. Name the parts of the *'PC equipment (Pigs. 118 
and 119), and their duties. 

A. 1. Control valve with its compartment reservoir ^ which 
corresponds in a general way to the triple valve of the old 
passenger brake equipments, and more closely to the dis- 
tributing valve of the ^^ET'^ Locomotive Brake. 

2. Two brake cylinders, one called the service cylinder 
and the other the emergency cylinder. The service cylinder 
alone operates in service applications, and both cylinders 
operate in emergency. 

3. Two storage reservoirs^ called the service and emer- 
gency reservoirs according to the brake cylinders with 
which they operate. 

4. A centrifugal dirt collector placed in the branch- 
pipe from brake pipe to control valve near the latter to 
prevent scale, sand and dirt from reaching the control valve. 

5. A branch-pipe air strainer screwed into thebranch- 
pipe connection of the control valve to take the place of the 
small wire strainer used in the quick action triple valves. 
(See No. 16, Fig. 5.) 

6. A conductor's valve, same as used with all passenger 
brake equipments, placed inside the car and connected to 
the brake pipe so that the brakes may be applied by the 
conductor in case of necessity. 

7. Various other details usually required in pas- 
senger brake equipments such as cut-out cocks, angle cocks, 
hose and couplings, dummy couplings, etc. 

8. Although not a fundamental part of the equip- 
ment, the automatic slack adjuster (see page 94) is usually 
applied to insure uniform piston travel. 

Q. How are the graduated-release and quick-recharge 
features obtained? 

A. By the air stored in the emergency reservoir. 

Q. How is greater certainty and uniformity in serv- 
ice action obtained? 



352 Air-Brake Catechism 

A. Slight brake pipe reductions cause the moving parts 
of the control valve to close the feed grooves without going 
to service position; after that, a necessary and proper re- 
duction must be made before the brakes will apply. 

Q. How is the quick rise in brake-cylinder pressure 
obtained? 

A. As soon as the control valve parts start toward 
service position, they move very promptly, and open large^ 
direct and unrestricted passages from reservoirs to brake 
cylinders. 

Q. How is service brake-cylinder pressure maintained 
during a stop? 

A. In the same way as on locomotives, by the applica- 
tion portion of the distributing valve. (See page 228.) 

Q. How is the service braking power limited to a 
certain amount? 

A. The volumes of the pressure chamber and application 
chamber of the control valve are fixed, and when their 
pressures become equalized, no higher service brake-cylinder 
pressure can be obtained. 

Q. What is the maximum brake-cylinder pressure in 
service with 110 pounds brake-pipe pressure? 

A. Eighty-six pounds. 

Q. What brake-pipe reduction will give this? 

A. Twenty-four pounds, the same as with the high speed 
brake. 

Q. How does this pressure of equalization in service 
compare with older equipments? 

A. It is much higher, the older equipments being de- 
signed to equalize at 50 pounds from 70-pound brake pipe, 
and being limited to 60 pounds by the high-speed reducing 
valve, or safety valve, when 110-pound brake pipe is used. 

Q. How is the "full emergency at any time" fea- 
ture obtained? 

A. Since the service and emergency parts of the control 



The ^'PC' Brake Equipment 353 

valve are entirely separate, and the operation of the quick- 
action portion depends only on the movement of its parts 
to emergency position (which always occurs when an emer- 
gency reduction of brake-pipe pressure is made) it follows 
that an emergency application can always be effected re- 
gardless of what applications may have previously occurred. 

Q. What is the purpose of the feature giving an 
automatic emergency application on depletion of brake- 
pipe pressure? 

A. It is a positive assurance against total loss of braking 
power due to pumps stopping, leakage, waste of air, or any 
other cause, because whenever brake-pipe pressure becomes 
reduced to a certain' point, the quick-action portion of the 
control valve opens up the brake pipe to the atmosphere, 
thereby causing an emergency application by means of the 
air remaining in the service and emergency reservoirs. 

Q. Can this kind of an emergency application be 
obtained in handling the brake valve without going to 
emergency position? 

A. Yes, if the engineer keeps on reducing brake-pipe 
pressure below full service reduction with the brake-valve 
handle in service position, he will eventually reach the point 
where the control valves v/ill automatically apply in emer- 
gency. 

Q. Is this good practice? 

A. No, it is very bad practice, and any engineer causing 
such an application shows that he does not understand how 
to properly handle the brake valve. 

Q. What is this feature of the ''PC equipment often 
called? 

A. The ^^over reductioii^^ feature. 

Q. Besides obtaining emergency at any time, what 
else is effected by separating the service and emergency 
features? 



351 Air-Brake Catechism 

A. It permits of the necessary flexibility in service opera- 
tion without in any way impairing the emergency features. 

Q. Why is a low total-leverage ratio possible with 
this equipment? 

A. The use of two brake cylinders per' car, combined 
with the high-service equalization pressure of 86 pounds, 
since for the same service braking power it is not necessary 
to multiply the higher c^^linder pressure so many times. 

Q. How is the control valve made less sensitive to 
small brake-pipe fluctuations than the triple valves? 

A. ^ A small drop in brake-pipe pressure will close the 
feed groove without causing anj^ application, so that unless 
the brake-pipe pressure becomes reduced to the point where 
an application ought to occur, there will be no ill effects 
from the small reduction. 

Q. How does this equipment cause a rapid rise in 
brake-pipe pressure during a release of the brakes? 

A. Very little air is taken from the brake pipe to re- 
charge until the pressure chamber of the control valve is 
charged to within five pounds of normal brake-pipe pressure; 
consequently nearl}^ all the air flowing into the brake pipe 
from the main reservoirs through the brake valve is utilized 
in raising the pressure in the small brake-pipe volume. As 
a result, brake-pipe pressure will rise as rapidly as the air 
can flow through the length of the train, without having 
to also recharge auxiliary reservoirs. 

Q. How is increased sensitiveness to release obtained? 

A. The control valve is so designed as to require a con- 
siderable differential to cause it to go to service position, 
while on the other hand a ver^^ small differential will cause 
the parts to move back to release position. Consequently 
in long trains where the rate of rise in brake-pipe pressure 
is Hkely to be slow, especially at the rear end, the control 
valve will release the brakes more readily than any triple 
valve. 



The "PC" Brake Eqi ipmext 355 

Q. Why is it considered desirable to introduce a fea- 
ture to transform the graduated release to direct re- 
lease? 

A. During the transition period, when cars are being 
equipped with this new brake, and they will for some time 
have to operate in trains with other cars having the older 
type of brake without the graduated release feature, it is 
considered best to use only the direct release on all cars 
until such time as they are all equipped with the graduated- 
release brake. 

The No. 3-E Control Valve. 

Q. What are the principal parts of the control valve? 

A. 1. Equahzing portion. 

2. Application portion. 

3. Emergency portion. 

4. Quick-action portion. 

Q. Referring to Figs. 120, 121, and 122, how are these 
parts assembled? 

A. The appHcation portion projects into the inside of 
the compartment reservoir from the front end, and the 
equalizing portion bolts onto the front end right on the 
application portion. The emergency and quick-action por- 
tions protrude up into the reservoir from the bottom, one 
on either side, the quick-action portion on the left and the 
emergency portion on the right. 

Q. How many chambers are there in the compart- 
ment reservoir, and what are they called? 

A. Three : the pressure chamber y application chamber , and 
the reduction-limiting chamber. 

Q. What are the duties of the equalizing portion? 

A. It corresponds in a general way to the equalizing 
portion of the distributing valve (page 228) or the old plain 
triple valve (page 21). It is directly affected by changes 
in brake-pipe pressure and controls, either directly or in- 



356 



Air-Brake Catechism 



directly, the charging of the reservoirs, the application of 
the brake in either service or emergency, and the release of 
the brake. 

Q. What are the duties of the application portion? 

A. It controls the flow of air from the service reservoir 
to the service cylinder, and the release of this cylinder. It 
has nothing to do with the emergencj^ reservoir or emer- 
gency brake cylinder. 

Q. What is the emergency portion for? 

A. It contains a double piston and slide valve, which 
controls the flow of air from the emergency reservoir to the 
emergency brake cylinder, and the release of that cylinder 
to the atmosphere. 

Q. What are the duties of the quick-action portion? 

A. It corresponds in a general way to the quick-action 
portion of a triple valve. It operates only in emergency 
applications, venting brake pipe air to the atmosphere 
(instead of to the brake cylinder), and closing the vent as 
soon as the desired brake-pipe reduction is made. 




Fig. 120. No. .3-E Control Valve. Side View. 



The ''PC" Brake Equipment 



357 



Q. What does Fig. 120 represent? 

A. It is a side view of the complete assembled control 
valve. 




LOJ 



Fig. 121. No. 3-E Control Valve. Front View. 



APPLICATION PORTION 



COMPARTMENT RESERVOIR 




EMERGENCY 
PORTION 



Fig. 122. No. 3-E Control Valve, Showing the Different 
Portions of the Valve. 



358 



Air-Brake Catechism 





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The "'PC'' Brake Equipment 



;59 



Q. What is Fig. 121? 

A. It is a front view of the control valve showing the 
equalizing portion. 

Q. What is shown in Fig. 122? 

A. It shows a side view of the control valve with the 
various parts separated to show their relative location. 

Q. What is shown in Figs. 123 and 124? 
A. An outline of the control valve showing the over-all 
dimensions and the pipe connections. 

Q. Where are all the pipe connections made? 

A. In the compartment reservoir, which is the only part 
rigidly attached to the car. 




I* PIPE 
EMER. PISTON EX. 



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EMER. CYLEX. 

Fig. 124. No. 3-E Control Valve, Outline. 



Q. What type of triple valve does the control valve 
resemble in this respect? 

A. The ^^pipeless" triple valves. 

Q. Referring to Figs. 125 and 126, what are the 
names of the detail parts of the control valve? 

A. Equalizing portion: 2, Equalizing Body; 3, Release 
Piston; 4, Release Slide Valve; 5, Release Slide Valve 
Spring; 6, Release Graduating Valve; 7, Release Graduating 



360 



Air-Brake Catechism 



Valve Spring; 8, Release Piston Cap Nut; 9, Release Piston 
Ring; 10, Release Cylinder Cap; 11, Release Cylinder-Cap 
Gasket; 12, Square Head Cap Screw; 13, Release Piston 
Graduating Sleeve; 14, Release Piston Graduating Spring; 
15, Release Piston Graduating Nut; 16, Check Valve; 17, 
Check- Valve Cap Nut; 18, Direct- and Graduated Release 
Cap; 19, Stud and Nut for Direct and Graduated Release 




90 92 137 93 154 

Fig. 125. No. 3-E Control Valve. Actual Section. 

Cap; 20, Equalizing Piston; 21, Equalizing Piston Ring 
(Large); 22, Equalizing Slide Valve; 23, Equalizing Slide- 
Valve Spring; 24, Equalizing Graduating Valve; 25, Equal- 
izing Graduating-Valve Spring; 26, Large Equalizing 
Cylinder Cap; 27, Large Equalizing Cylinder-Cap Gasket; 
28, Square Head Cap Screw; 29, Equahzing Piston Stop 
Sleeve; 30, Equalizing Piston Stop Spring; 31, Equalizing 
Graduating Nut; 32, Equalizing Piston Ring (Small); 33, 



The "PC"' Brake Equipment 



361 



!3 DRILL ■ 



I PIPE 
SER.CYLiX, 

V'PIPE 
^SER. RES. 




Fig. 126. No. 3-E Control Valve, Actual Section. 

Small Equalizing Cylinder Cap; 34, Gasket for Small Equal- 
izing Cylinder Cap; 35, Square Head Cap Screw; 36, Cap 
Nut for Small Equalizing Cylinder Cap; 37, Small Equaliz- 
ing Piston Bush; 38, Service-Reservoir Charging Valve; 39, 
Charging-Valve Piston Ring; 40, Charging- Valve Piston 
Ring; 41, Charging-Valve Seat; 42, Charging-Valve Washer; 
43, Internal Charging-Valve Nut; 44, External Charging- 
Valve Nut; 45, Gasket for Direct and Graduated Release 
Cap. 

Application Portion: 75, Body; 76, Piston Stem; 77, Pis- 
ton Ring (Small); 78, Piston Head; 79, Piston Seal; 80, Pis- 
ton Ring (Large); 81, Piston Follower; 82, Piston Packing 
Leather; 83, Piston- Packing Leather Expander; 84, Piston 
Nut; 85, Piston Cotter; 86, Exhaust Valve; 87, Exhaust 
Valve Spring; 88, Application Valve; 89, Application-Valve 



362 



Air-Brake Catechism 



Spring; 90, Application-Piston Bolt; 91, Spring Box; 92, 
Piston-Spring Sleeve; 93, Piston Spring; 94, Graduating 
Nut; 95, Application-Valve Cover Gasket; 97, Square Head 
Screw for Application-Valve Cover. 



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FACE VIEW 
GRADUATING VALVE 



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PLAN VIEW 



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FACE VIEW 
EQUALIZING SLIDE VALVE 




EQUALIZING SLIDE VALVE SEAT 

Fig. 127. Equalizing Graduating Val^t:, Slide Valve, and Slide 

Valve Seat. 



The *TC" Brake Equipment 



3G3 



Emergency Portion: 107, Body; 108, Piston (Complete); 
109, Piston Ring; 110, Slide Valve; 11, Slide-Valve Spring; 
112, Small Cylinder Cap; 113, Large Cylinder Cap; 114, 
Small Cylinder-Cap Gasket; 115, Large Cylinder-Cap 
Gasket; 116, Piston Spring; 117, Square Head Cap Screw 
for Small Cylinder Cap; 118, Oval Fillister Head Cap 
Screw; 119, Emergency Piston Bush. 

Quick Action Portion: 130, Body; 131, Piston (Complete) ; 
132, Piston Ring; 133, Quick-Action Valve; 134, Quick- 
Action Valve Seat; 135, Quick- Action Valve Nut; 136, 
Quick-Action Valve Spring; 137, Quick-Action Valve-Cap 
Nut; 138, Quick-Action Valve Cover; 139, Quick-Action 



FACE VIEW 
RELEASE GRADUATING VALVg 





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FACE VIEW 
RELEASE SLIDE VALVE 



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RELEASE SLIDE VALVE SEAT 

Fig. 128. Release Graduating Valve, Slide Valve^ and Slide 

Valve Seat. 



364 



Air-Brake Catechism 



Closing Valve; 140, Quick- Act ion Closing Valve Spring; 
141, Cover Cap Nut; 142, Cover Gasket; 143, Square Head 
Cap Screw for Cover. 

Reservoir: 153, Triple-Compartment Reservoir; 154, Cap 
Nut; 155, Stud with Hex. Nut; 156, Stud with Hex. Nut; 
157, Emergency Cylinder Gasket; 158, Quick-Action 
Cylinder Gasket; 159, Large Reservoir Gasket; 160, Equal- 
izing Cylinder Gasket. 



LARGE PISTON END 



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LARGE PISTON END 



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Fig. 120. Emergency Slide Valve and Slide Valve Skat. 



Q. What do Figs. 127, 128 and 129 represent? 

A. They show views of the face of the equalizing gradu- 
ating valve, slide valve, and slide-valve seat; the release 
graduating valve, slide valve, and slide-valve seat; and the 

emergencv slide valve and slide-valve seat. 

Q. To what chambers and parts do these various 
ports connect? 

A. Equalizing Slide-Valve Seat: 1, Emergency Reser- 
voir Check Valve (under side); 2, Brake Pipe; 3, Direct and 
Graduated Release Cap Topen only when cap is adjusted 
for graduated release); 4, Reduction Limiting Chamber Ex- 
haust; 5, Small End (Chamber G) of Service Reservoir 
Charging Valve; 6, Reduction Limiting Chamber; 7, Large 
End (Chamber K) of Service Reservoir Charging Valve; 8, 



The ^TC" Brake Equipment 365 

Release Slide-Valve Chamber (Chamber E); 9, Application 
Chamber and Front of Application Piston (Chamber C); 
10, Emergency Reservoir; 11, Pressure Chamber; 12, 
Slotted Port; 27, Small Equahzing Piston (Chamber F). 

Release Slide-Valve Seat: 13, Large Emergency Piston 
(Chamber P); 14, Small Emergency Piston (Chamber S); 
15, Direct and Graduated Release Cap (open only when cap 
is adjusted for graduated release); 16, Emergency Piston 
Exhaust; 17, Direct and Graduated Release Cap (open 
only when cap is adjusted for direct release) ; 18, Application 
Chamber Exhaust, also Direct and Graduated Release Cap 
(the latter open only w^hen cap is adjusted for Direct Re- 
lease); 19, Application Chamber; 20, Quick-Action Closing 
Valve; 21, Emergency Reservoir; 22, Small Equahzing 
Piston (Chamber F). 

Emergency Slide-Valve Seat: 23, Service Brake Cylinder; 
24, Back of Application Piston (Chamber M); 25, Emer- 
gency Cylinder Exhaust; 26, Emergency C3dinder. 

Q. What do Figs. 130 to 144 represent? 

A. They are diagrams of the control valve and compart- 
ment reservoir with the movable parts in different positions 
as they occur in operation. The actual form of the parts 
has been entirely disregarded, and the ports are shown in 
the simplest manner possible to indicate the connections 
made. In all except Fig. 130, only those ports which are 
in action are shown. 

Q. What position of the control valve is illustrated 
in Fig. 130, and when does it occur? 

A. ^^NormaF^ position, occupied by the various parts 
of the valve when properly assembled and before air pressure 
is admitted to the brake system. It indicates the relation 
of all the ports and detail parts of the valve. 

Q. What chambers are always subject to brake-pipe 
pressure? 



366 



Air-Brake Catechism 




The '-VC" Brake Eqiii-ment 



3G- 




36S Air-Brake Catechism 

A. Chamber A above the equahzing piston; chamber B 
above the release piston; and the chamber below the quick- 
action valve. 

Q. What chamber is the service brake cylinder 
always connected with? 

A. Chamber above the exhaust valve. 

Q. What chambers is the service reservoir always 
connected with? 

• A. Chamber A^ above the application valve, and chamber 
H around the center of the service reservoir charging valve. 

Q. What chamber is the emergency cylinder always 
connected with? 
A. Chamber T above the quick-action closing valve. 

Q. What chamber is the emergency reservoir always 
connecting to? 
A. Chamber R over the emergency slide valve. 

Q. When the brake system is being charged and air 
is admitted to the brake pipe, what takes place in the 
control valve? (See Fig. 131.) 

A. Air enters the control valve at the brake-pipe con- 
nection and passes to chambers A and B, and through feed 
groove I to chamber E. As soon as the pressure in chamber 
A is sufficient to overcome the resistance of the equalizing 
stop spring, the equahzing piston is forced down until the 
lower end seats on the gasket in chamber F. Air can then 
flow from chamber B past the equalizing check valve into 
chamber D. From chamber D, the air flows through the 
equalizing slide valve past the emergency reservoir check 
valve, and from there it goes in two directions: First, to 
chamber R and the emergency reservoir; second, through 
the equalizing slide valve to the service reservoir check 
valve and the service reservoir, and through the graduated 
release cap and release slide valve to chamber E (which is 
also charged through the small feed groove i). This last 
mentioned connection is made only when the graduated 



The ^TC" Brake Equipment 369 

release cap is in the graduated release position; when that cap 
is in the direct release position, chamber E is charged only 
by feed groove i. Air also flows from chamber E through 
the equalizing slide valve to chamber K below the service 
reservoir charging valve, and also the pressure chamber. 
Since the pressure in chambers D and E at this time is 
practically equal, and the area of the charging valve facing 
chamber K is larger than that in chamber G at the top, the 
charging valve will be held in its upper position until the 
service reservoir, which connects at all times with chamber 
H around the middle of the charging valve, is charged to 
the same pressure as that in chamber E and the pressure 
chamber, 

Q. What other connections are made in the Release 
Position? 

A. Chamber F below the equalizing piston is connected 
through the release sUde valve with the emergency piston 
exhaust and atmosphere^ thus holding the equalizing piston 
firmly in release position. Chamber S below the emergency 
piston is also connected to the same exhaust opening, there- 
by holding the emergency piston firmly in its proper posi- 
tion. The reduction limiting chamber is connected through 
the equahzing slide valve to the reduction limiting chamber 
exhaust and atmosphere. The application chamber and 
chamber C in front of the application piston are connected 
through the release slide valve and graduating valve with 
the application chamber exhaust and atmosphere. The 
service brake cylinder is connected through the exhaust 
slide valve of the application portion with the service brake- 
cylinder exhaust to the atmosphere. And the emergency 
brake cylinder is connected through the emergency slide 
valve to the emergency cylinder exhaust and the atmos- 
phere. The small cavity in the release graduating valve is 
always connected to the emergency piston exhaust so as 



370 



Air-Bkaivk Catechism 




The "PC" Brake Equipment 



371 




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372 Air-Brake Catechism 

to insure a sufficient pressure on the graduating valve to 
hold it to its seat. This cavity performs no othet service. 

Q. After the equipment is fully charged and a service 
reduction of brake-pipe pressure is made, what occurs 
in the control valve? (See Figs. 132 to 134.) 

A. The pressure in chambers A and B will be reduced 
'below that in chambers D and E tending to force the pistons 
and their valves upward. But since the chamber F, below 
the equalizing piston, is open to the atmosphere, through 
the release slide valve and the emergency piston exhaust, 
the release piston will move first upward until it strikes the 
graduating spring sleeve. There is a small amount of lost 
motion between the release piston and graduating valve, 
and a somewhat greater lost motion between the piston and 
the slide valve, so that during the first upward movement 
of the piston, the slide valve remains in its release position 
keeping chamber F open to the atmosphere, which insures 
that the equalizing piston will not move upward until after 
the release piston. Thus the release piston first moves up- 
ward as above described to preliminary service position, 
closing feed groove i, and the port leading from the appli- 
cation chamber to the atmosphere. It also closes the con- 
nection between chamber F and the atmosphere and makes 
connection between that chamber and chamber E. (See 
Fig. 132.) This results in permitting air from the pressure 
chamber to raise the pressure-chamber check valve and flow 
to chamber Fj balancing the pressures in chambers F and D 
above and below the small end of the equalizing piston. 
This permits the equalizing piston to move upward until 
the shoulder on the piston stem strikes the slide valve, as 
shown in Fig. 133, when a connection is momentarily made 
between the emergency reservoir and chamber D, which 
prevents a drop in pressure in that chamber due to the up- 
ward movement of the equalizing piston. (The volume of 



The ^^PC'^. Brake Equipment 



IM'd 




374 AiR'Brake Catechism 

chamber D is so small compared with the displacement of 
the piston as to require this arrangement.) At the same 
time, chamber D and the pressure chamber are connected 
through the equalizing slide valve and graduating valve to 
keep their pressures equal. Of course, this position is occu- 
pied only an instant, as the pressure in chamber D causes 
the equalizing piston to continue its upward movement 
carrying the slide valve and graduating valve with it to the 
service position where the piston strikes its graduating sleeve, 
as shown in Fig. 134. 

In this position, chambers F and D are connected by 
a feed port around the small end of the equalizing piston. 
The pressure chamber is connected to chamber D: First, 
directly through the equalizing slide valve; second, past the 
pressure chamber check valve and chamber E through the 
release slide valve and equahzing slide valve, also through 
chamber F. From chamber Z), air flows through the equal- 
izing slide valve to the application chamber and chamber C 
on the face of the application piston, forcing the latter to 
the application position. This closes the service cylinder 
exhaust and opens connection between the service reservoir 
and chamber A^ to the service brate cylinder, thus applying 
the brakes. The air flowing to the service brake cylinder 
also flows by way of the emergency slide valve to chamber 
Af, thereby equalizing the pressures in chambers M and 0, 
The reduction-limiting chamber and the emergency brake 
cylinder are still connected to the atmosphere as in release 
position. 

Q. If the brake-pipe reduction made was fifteen 
pounds, how long will the parts of the control valve 
remain in service position? 

A. Until the pressure in chambers D and E and the 
pressure chamber falls slightly below that in the brake pipe 
and chambers A and B. 



The 'TC Brake Equipment 375 

Q. What will occur then? 

A. The pistons and graduating valves will move down 
until the shoulder on the piston stem strikes the slide valve 
to Service Lap position. This closes communication be- 
tween the pressure chamber and the application chamber, and 
holds whatever pressure there is in chamber C and the 
application chamber. As soon as the pressure in the service 
brake cylinder and chambers C and M is slightly above 
that held in chamber C, the application piston will move 
back and close communication between the service reservoir 
and service brake cylinder as shown in Fig. 135. 

Q. If brake)'Cylinder pressure becomes reduced 
through leakage or otherwise, what will happen? 

A. The application valve will open and admit enough 
air from the service reservoir to the brake cyl nder to rein- 
state the pressure, in the same manner as with the distrib- 
uting valve of the ^^ET'' equipment (see page 241). Con- 
sequently brake-cylinder pressure is maintained practically 
constant within the capacity of the service reservoir. 

Q. What does the movement of the release piston and 
graduating valve to lap position accomplish? 
A. It performs no functions whatever. 

Q. What other parts of the control valve operate at 
this time? 
A. All the other parts remain as in service position. 

Q. If the engineer makes a full-service reduction, will 
the parts go to service lap as above described? 

A. No, they will remain in service position. 

Q. What is a full-service reduction with this equip- 
ment? 

A. Twenty-four pounds, just as with any other brake 
equipment using 110 pounds brake-pipe pressure. 

Q. If the engineer makes more than a full-service 
reduction, what will happen? 
A. The pressure in chambers A and B will fall below 



376 



Air-Brake Catechism 




The "FC' Brake Equipment 377 

that in chambers D and E^ so that the equalizing piston is 
forced upward beyond the service position, compressing its 
graduating spring, to the position called the over-reduction 
position as shown in Fig. 136. The release piston does not 
move upward because its graduating spring is heavier and 
requires a considerably greater differential to compress it. 

Q. What cannections are made in the over-reduction 
position? 

A. Chamber D is now connected through the equalizing 
slide valve with the reduction-limiting chamber which has 
heretofore been maintained at atmospheric pressure, and 
air will now continue to expand from the pressure chamber 
(and chambers D arid E) into the reduction-limiting chamber, 
at the same rate that in service position it expanded into 
the application chamber. The application chamber and 
chamber C are also connected to chamber G above the 
charging valves, while chamber K below the charging valve 
is connected to chamber D through the equalizing shde 
valve. The other connections are as in Service Position. 

Q. What change takes place in application-chamber 
pressure during this time? 

A. None. Any reduction in application-chamber pres- 
sure is reinstated by air leaking by the small end of the 
charging valve from the service reservoir. 

Q. What position must the charging valve have at 
this time? 

A. Since the pressure in chamber G remains constant 

while that in chamber K (and chamber D) is reducing, it 

follows that the charging valve will be held firmly down 

against its lower seat. 

Q. Suppose that only a small over reduction in brake- 
pipe pressure is made, how long will the parts of the 
control valve remain in over-reduction position? 

A. Until the pressure in chambers D and E and the 
pressure chamber falls slightly below that remaining in the 



378 



Air-Brake Catechism 




i 



The ^TC^' Brake Equipment 379 

brake pipe, when the equaUzing piston and graduating valve 
will be forced downward to the over-reduciion lap position, 
as shown in Fig. 137. This closes connection between the 
pressure chamber and the reduction-limiting chamber pre- 
venting any further flow of air to the latter. 

Q. Are any other changes in port connections made 
in over-reduction lap position? 

A. The equalizing graduating valve closes connection 
between chambers D and K, and the release piston and 
graduating valve move downward, closing connection be- 
tween chambers E and D, These closures are, however, 
only incidental and have no effect on the existing pressures. 
All other parts and pressures remain as in over-reduction 
position. 

Q. How long can an over -reduction be made in this 
manner? 

A. Until the pressure chamber and reduction-limiting 

chamber become equalized in pressure. 

Q. If the reduction in brake-pipe pressure is carried 
beyond this point, what will happen? 

A. Since the pressure in chambers D and E cannot re- 
duce any further, a sufficient differential will be built up 
on the two sides of the equalizing and release pistons to 
force them to emergency position. 

Q. What are the pressures of equalization between 
the pressure chamber and reduction-limiting chamber? 

A. Sixty pounds when carrying 110 pounds brake-pipe 
pressure, and 35 pounds when carrying 70 pounds brake- 
pipe pressure. 

Q. What brake-pipe reductions, therefore, are nec- 
essary to reach this point? 

A. Fifty-pound reduction from 110, or 35-pound re- 
duction from 70. 

Q. How do these reductions compare with those re- 
quired for a full-service application? 



380 



Air-Brakb Catechism 




The "PC' Brake Equipment 381 

A. They are just about twice as great. 

Q, With the parts of the control valve in either ser- 
vice lap or over-reduction lap position, what occurs when 
the engineer releases the brakes? 

A. The increase in brake-pipe pressure in chambers A 
and B over that existing in chambers D and E will cause 
the pistons and their valves to move downward. The 
equalizing piston moves first, the parts being designed to 
require a somewhat greater differential to move the release 
piston and its valve. Consequently the parts will first 
assume the position known as preliminary release^ as shown 
in Fig. 138, when the equalizing piston strikes the piston 
stop at its lower end. Chamber F is then connected to the 
pressure chamber by way of the equalizing slide valve, so 
that the pressure in chamber F, in addition to the force of 
the stop spring, insures that the equalizing piston and its 
valves will hestitate in this position. At the same time, 
chamber E is connected through the equalizing slide valve 
and graduating valve to the reduction-limiting chamber 
exhaust, which causes a momentary reduction of pressure 
in chamber Ej thereby positively insuring that the release 
piston is forced to the release position, as shown in Fig. 139. 
Consequently the preliminary release position is only occu- 
pied for an instant, and is the first step in the movement 
of the parts to the full-release position. 

Q. What is the second step in the movement of the 
control-valve parts to full-release position? 

A. The venting of air from chamber E through the 
equalizing slide valve and graduating valve and reduction- 
limiting chamber exhaust, results in forcing the release 
piston and its valves promptly to release position while the 
equalizing piston and its valves hesitate momentarily in the 
preliminary release position as shown in Fig. 139. This 
position is known as Secondary Release position, in which 



382 



Air-Brake Catechism 




The '-PC" Brake Eqcipment 



383 




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384 AiR-BuAKE Catechism 

connection is made between chamber F through the release 
shde valve to the emergency-piston exhaust. Also the 
pressure chamber \^ connected through the equalizing slide 
valve to the same port which connects chamber F to the 
atmosphere. At first the pressure in the pressure chamber 
tends to hold up the pressure in chamber F to insure that 
the release piston will move completely to the release 
position, but as these chambers are connected to the at- 
mosphere through small ports, their pressure will reduce, 
thereby causing the equalizing piston to move on down- 
ward. In this movement, the equalizing slide valve restricts 
and finally stops the flow of air from the pressure chamber 
to chamber F, which results in the latter becoming rapidly 
reduced to atmospheric pressure, and causing the equalizing 
piston and its valves to move positively to release position, 
as shown in Fig. 140. 

Q. Is the control valve now in full release position? 

A. Not quite, as the charging valve is still closed. 

Q. Why is this? 

A. So as to insure that the pressure chamber will be 
almost completely recharged before the service reservoir 
begins to recharge. 

Q. What connections are made in the gralduated- 
release position as shown in Fig. 140? 

A. The application chamber and chamber C are con- 
nected through the release slide valve and graduating valve 
to the application-chamber exhaust and the atmosphere. 
This causes the application piston and its valves to move 
to the release position, connecting the service brake cylinder 
to the exhaust, as in the distributing valve. Air can also 
flow from chamber B past the equalizing check valve to 
chamber 2), and through the feed groove i to chamber E. 
From chamber E^ air can flow through the equahzing slide 
valve to chamber K below the charging valve, and to the 



The ''PO" Rrake EQiir.MENT 



385 







386 Air-Brake Catechism 

pressure chamber. The emergency reservoir is connected to 
chamber G above the charging valve, and through the 
graduated release cap to chamber E, 

Q. How long will the parts remain in this position? 

A. If a complete release of the brakes is desired, the 
pistons and their valves will remain permanently in this 
position until another application of the brakes. As soon 
as the air flowing into chamber E, through feed groove i 
and from the emergency reservoir, raises its pressure to 
within five pounds of that remaining in the emergency 
reservoir (which has been held during the application 
charged to its full pressure) the pressure in chamber Kj 
acting on the large end of the charging valve, will overcome 
the pressure in chamber G acting on the small end, and will 
cause it to move to its upper seat, connecting the emergency 
reservoir to the service reservoir, as well as the other con- 
nections described under Release Position and shown in 
Fig. 131. This will result in a complete release of the brakes 
and recharging of all chambers and reservoirs. 

Q. If a graduated release is desired and the brake- 
pipe pressure is only partly reinstated, what will occur 
in the control valve? 

A. Assuming that the graduated-release cap is in the 
graduated-release position, the connections between the 
emergency reservoir and chamber £* through the equalizing 
slide valve, graduated-release cap and release slide valve 
will tend to raise the pressure in chamber E and the pressure 
chamber above the partly reinstated pressure in chamber B, 
As soon as the difference in pressure between these two 
chambers is sufficient to overcome the frictional resistance, 
the release piston and graduating valve are forced upward 
to the graduated-release lap position, shown in Fig. 141. 

Q. What change in port connections occurs in grad- 
uated release lap position? 



The "PC" Brake Equipment 



38' 




388 Air-Brake Catechism 

A. The movement of the release-graduating valve cuts 
off connection between the emergency reservoir and 
chamber E, thereby preventing any further recharging of 
that chamber and the pressure chamber. It also closes con- 
nection between the application chamber and its exhaust 
outlet, which entraps a certain amount of pressure in 
chamber C This pressure causes the application piston 
and its valves to move to lap position and stop the exhaust 
of service brake-cylinder air. 

Q. If the graduated-release cap is in the direct re- 
lease position, how will it affect the operation of the 
control valve during^ release? (See Fig. 142). 

A. At such times there is no connection from the emer- 
gency reservoir to chamber E or the pressure chamber; conse- 
quently the pressure chamber is charged only by the air 
coming from the brake pipe through feed groove i into 
chamber E which passes through the equalizing slide valve 
to the pressure chamber. As a result, the pressure in chamber 
E cannot exceed that in the brake pipe (from which it gets 
its air) and there can never be any tendency for the release 
piston to move upward again as in graduated release. 

Moreover, in this position of the graduated-release cap, 
the application chamber and chamber C are connected 
through a port in the release slide valve directly to the 
atmosphere at the application chamber exhaust, regardless 
of the position of the release piston and graduating valve, 
so long as the release slide valve is in release position. This 
insures a complete release of brake-cylinder pressure when- 
ever the valve goes to the release position. 

Q. When will the control valve go into the emer- 
gency position? 

A. Whenever the brake-pipe pressure is reduced more 
rapidly than the predetermined rate for service applications; 
or when the brake-pipe reduction is continued below the 



The 'TC" Brake Equipment 



389 




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390 Air-Brake Catechism 

point at which the pressure and reduction-limiting chambers 
equalize Clover-reduction'' feature); or whenever leakage 
or any other cause reduces brake-pipe pressure below that 
point (protection feature). 

Q. What occurs in the control valve due to an emer- 
gency application? (See Figs. 143 and 144). 

A. The large difference in pressures on the two sides of 
the equalizing and release pistons causes them both to move 
upward to the extreme position against their cylinder-cap 
gaskets. In this position air may flow directly from the 
emergency reservoir to chamber E^ thence to the under 
side of the quick-action closing valve. Since chamber T, 
above the quick-action closing valve, is always in com- 
munication with the emergency brake cylinder, and since 
at this time there is no pressure in that cylinder, the air 
from the emergency reservoir will force the quick-action 
closing valve upward, and flow into chamber W, forcing 
the quick-action piston downward and opening the quick- 
action valve, thus venting brake-pipe pressure to the at- 
mosphere through the quick-action exhaust. This causes 
the rapid transmission of serial quick-action through the 
train as with the ordinary quick-action triple valve, except 
that the venting takes place to the atmosphere instead of 
to the brake cylinder. 

Q. What other connections are made in the control 
valve, in an emergency application? 

A. Air from the emergency reservoir also flows from 
chamber E directly to the application chamber and chamber 
C, thereby forcing the application piston and its valves to 
the application position, which connects the service reservoir 
to the service brake cylinder. At the same time, chamber 
P above the large emergency piston is connected through 
the release slide valve with the emergency-piston exhaust, 
which allows the emergency-reservoir pressure in chamber 



The "PC" Brake Equipment 



391 




392 



Air-Brake Catechism 




I 



The ^*rc^' Brake Equipment 393 

R to force the pistons and slide valve upward to the extreme 
position. 

What connections are made by this movement of 
the emergency slide valve? 

A. 1. Emergency reservoir is connected past the end 
of the slide valve with the emergency brake cylinder. 

2. A port through the slide valve connects the emer- 
gency and service reservoirs so that their pressures become 
equalized in both brake cylinders. 

3. A cavity in the slide valve connects chamber M 
between the large and small application pistons to the atmos- 
phere at the emergency-cylinder exhaust. This last men- 
tioned connection insures a quick and positive movement 
of the application piston and its valves to the application 
position. 

Q. Are there any other connections made in emer- 
gency? 

A. The pressure chamber is connected through the equal- 
izing slide valve with chamber D and past the pressure 
chamber check valve with chamber E; also the reduction^ 
limiting chamber is connected with chamber D through the 
equahzing sUde valve. 

Q. What is the purpose of these connections? 

A. They perform no particular function except to insure 
pressure, acting on all slide valves so as to hold them to 
their seats and provide for the equalization of all chambers, 
reservoirs, etc. 

Q. Do all parts of the control valve remain in the 
position just described throughout an emergency appli- 
cation? 

A. No. The quick-action valve closes. 

Q. How does this occur? 

A. Since all reservoirs and cylinders become equalized 
in pressure, the pressures above and below the quick-action 



394 Air-Brake Catechism 

closing valve become equal. This allows the spring to seat 
the quick-action closing valve. The pressure in chamber W 
then reduces by air flowing to the atmosphere through the 
small port in the quick-action piston, and the quick-action 
exhaust. This allows the spring under the quick-action 
valve to force both it and the piston upward till the valve 
is seated. 

Q. What is the purpose of this closing of the quick- 
action valve? 

A. It closes connection between the brake pipe and the 
quick-action exhaust so that when a release is made, the 
brake-pipe pressure will not escape to the atmosphere and 
interfere with the release. 

Q. Do any other parts of the control valve change 
poiAtion in emergency? 

A. No. 

Q. In releasing after an emergency, how does the 
control valve operate? 

A. Just the same as after any other application and as 
described under ^^Release and Recharging.'' 

BRAKE CYLINDERS. 

Q. What does Fig. 145 illustrate? 
A. The type of brake cylinder used with the ''PC" 
equipment. 

Q. In what way does it differ from that used with 
previous equipments? 

A. Only in the pressure head which does not have any 

seat for a triple valve, but is a plain, flat head except for the 

slack adjuster lug. 

Q. Are both service and emergency brake cylinders 
just alike? 

A. They are always the same type but not always the 

same size. Very often the emergency brake cylinder is one 

size smaller than the service cylinder. 



The ^TC Brake Equipment 



395 



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396 Air-Brakb Catechism 

Q. What determines the size of each? 

A. The weight of the car and the desired increase of 
emergency braking power over service. If the emergency 
should be twice that of the service, both cyhnders are made 
the same size. Otherwise they are proportioned to give 
the desired relation between service and emergency. 

Q. How are the cylinders placed on the car? 

A. Directly opposite each so that the two sets of cylinder 
levers are symmetrical and connect by links of equal length 
to the same top rod at each end. (See Figs. 118 and 119.) 
Sometimes the cylinders point in the same direction, and 
sometimes in opposite directions; the latter is usually more 
convenient for hand-brake connection, while the former 
makes the slack-adjuster connections somewhat simpler. 
Which arrangement to use depends on the constr^iction of 
the car and the location of the apparatus. 

Q. Is the slack adjuster a regular part of this equip- 
ment? 

A. No, but an automatic slack adjuster for each brake 
cylinder is considered as about essential to this equipment, 
and always should be included. 

Q. How are the slack adjusters connected to the 
cylinder? 

A. Both adjusters are connected to the service brake 
cylinder so that they will both always operate at the same 
time and an equal amount. 

GENERAL. 

Q. How should an engineer handle this brake? 

A. Practically the same as with cars having the old 
quick- action brake. 

Q. What noticeable difference exists? 

A. An over-reduction will result in an emergency appli- 
cation if the reduction is continued below 60 pounds with 



The ^TC^' Brake Equipment 397 

110-pound brake pipe, or 35 pounds with 70-pound brake 
pipe. 

Q. What should be done to cut out this brake on a 
car whenever necessary? 

A. Close the ci;it-out cock in the brake-pipe branch to 

the control valve, and bleed both reservoirs. 

Q. Since both sets of cylinder levers are connected 
to the same pull rods, how does a service application 
affect the emergency cylinder? 

A. The emergency cylinder lever will move exactly as 
the service cylinder lever, but as the emergency-cylinder 
piston rod is provided with a slotted crosshead, the move- 
ment of the piston rod end of the emergency-cylinder lever 
does not cause any movement of the piston in that cylinder. 

Q. What important point should be noted from this 
fact? 

A. That the emergency-cylinder piston being in release 
position does not necessarily indicate that the brakes are 
released. To actually determine this, look at the ends of 
either the service or emergency-cylinder levers. 

Q. In adjusting the automatic slack adjusters, what 
is especially necessary to bear in mind? 

A. That the crossheads of both adjusters must be left 
at the same distance from their respective cylinder heads, 
so that the piston travel of both cylinders in an emergency 
application will be the same. 

Q. Where is the quick-action exhaust located? 
A. It is the one-inch pipe tapped opening in the bottom 
of the control-valve reservoir. 

Q. What should be done in the event of a continual 
blow at this opening? 

A. Make an emergency application, then release; if 
the blow continues, the quick-action valve leaks, and the 
quick-action portion (on the left when facing the equalizing 



398 Air-Brake Catechism 

portion) should be removed and replaced with one in proper 
condition. 

Q. Where is the application-chamber exhaust? 

A. It is the 3^-inch pipe tapped opening on the left side 
of the control-valve reservoir. 

Q. If a blow occurs at this opening, with brake either 
applied or released, what should be done? 

A. A new or repaired equalizing portion should be sub- 
stituted, as the release slide valve, or graduating valve, 
needs attention. 

Q. Where is the reduction limiting* chamber exhaust? 

A. It is the ^-inch pipe tapped opening on the left-hand 
side of the equalizing portion. 

Q. If a blow is heard at this exhaust in either re- 
lease or service position, what does it indicate? 

A. That the application portion is defective and should 
be replaced by a new, or repaired one. 

Q. If the blow occurs only after a 30-pound brake- 
pipe reduction^ wh^t is indicated? 

A. , That the emergency-reservoir check valve is de- 
fective, and another should be substituted. 

Q. Where is the emergency-reservoir check valve 
located? 

A. ^ It is the middle check valve in the equalizing portion. 

Q. If this blow at the reduction-limiting chamber 
exhaust continues all the while, what is the trouble? 

A. It indicates that the equalizing portion is defective 

and should be replaced. 

Q. Where is the emergency-piston exhaust? 
A. ^ It is the ^-inch pipe tapped opening on the right- 
hand side of the equalizing portion. 

Q. What should be done if a blow is heard at this 
exhaust opening? 

A. Make a 15-pound reduction, and lap the brake-valve 
handle. If the blow stops, it indicates that either the emer- 



The 'TC- Brake Equipment 309 

gency piston or the seal on the small end of the equalizing 
piston is defective. If the blow continues, it indicates a 
defective equalizing portion. In either case another portion 
in good order should be substituted. 

Q. Where is the service brake-cylinder exhaust lo- 
cated? 

A. It is the ^-inch pipe tapped opening on the left-hand 
side of the control-valve reservoir. 

Q. What does a hard blow at this exhaust indicate? 

A. If it occurs when the brakes are applied, it indicates 
a defective application portion; if when the brakes are 
released, it may .be either the application portion or the 
emergency portion that is defective. In either case another 
portion should be substituted. 

Q. Where is the emergency-cylinder exhaust? 
A. It is the 3^-inch pipe tapped opening on the bottom 
of the control-valve reservoir. 

Q. What does a hard blow at this exhaust indicate? 
A. It indicates a defective emergency portion, requiring 
the substitution of another in good order. 

Q. If the changing of the portions does not eliminate 
the trouble what should be done? 

A. Examine the gaskets between the portions to see if 

any defect exists in them. 

Q. When removing the application, emergency, and 
quick-action portions, what should be done with the 
gaskets? 

A. They should be left on the reservoir. 
Q. When removing the equalizing portion, where 
should the gasket be left? 

A. On the application portion, unless the latter is to be 
shipped to or from a repair point. 

Q. What general rule should be observed in apply- 
ing gaskets? 



400 Air-Brake Catechism 

A. They should be carefully exammed to see that no 
ports are restricted, or that the gasket is not broken or 
damaged between ports. See that the nuts are all tight 
so that a good bearing exists all around. 

Q. Where is the direct and graduated-release cap 
located? 

]A. On the front of the equalizing portion in the center, 
held in place by a single stud. 

Q. How should this cap be set? 

A. With the pointer on the cap toward either the words 
'^direct release^' or ^'graduated release'' (which are cast on 
the front of the portion) according to the instructions issued 
by the railroad. 

LUBRICATION OF THE CONTROL VALVE. 

Q. In lubricating the equalizing portion, what is the 
first thing to be done? 

A. Carefully wipe off the bearing surfaces with a soft 
cloth, or some soft material without lint, thoroughly remov- 
ing all oil, gum or grease from the slide valves and seats. 

Q. What next should be done? 

A. With a stick about 8 inches long, having a pad of 
chamois skin glued to one end, dip the chamois in a high 
grade of very fine dry (not flake) graphite, the best that can 
be obtained, and rub it on the face of the slide valves, gradu- 
ating valves, their seats, and the upper part of the slide- 
valve bushing where the slide-valve spring bears; rub into 
the surfaces thoroughly so as to make as much as possible 
adhere and fill in the pores of the brass, leaving a very thin 
light coating of graphite on the seats. 

Q. Should any oil or grease be used? 

A. No. Care should be taken that no oil or grease comes 
in contact with the slide valves or their seats, and in hand- 



The 'TC' Brake EguirMEXT 401 

ling, the fingers should not touch the lubricated surfaces, 
as moisture will tend to remove the graphite coating. 

Q. How should the pistons be lubricated? 

A. After replacing the pistons ancl slide valves in the 
equalizing portion, they should be moved to release position 
and a little good oil or graphite grease applied to the surfaces 
of the piston bushings. The pistons should then be moved 
back and forth several times to insure a proper distribution 
of the lubricant over the working surface. Any excess of 
lubricant should be removed with a cloth. 

Q. How should the application portion be lubricated? 

A. The slide valves and their seats should be cleaned 
and sparingly lubricated with graphite grease. The appli- 
cation piston and cylinder should be thoroughly cleaned 
and lubricated with graphite brake-cylinder lubricant. 

Q. How should the emergency portion be lubricated? 

A. 1. After thoroughly cleaning the bearing surfaces, 
remove the top cover and take out the loose fitting cylinder 
bushing. 

2. Lubricate the large piston with a few drops of a good 
grade of triple-valve oil, applying same sparingly to the 
slide valve, then enter the latter into the portion. 

3. Lubricate the slip bushing for the small emergency 
piston, applying a few drops of triple-valve oil to the inner 
circumference. 

4. Apply the bushing to the portion and belt on top 
cover. 

5. Move the slide valve to release position and put a few 
drops of oil on the walls of the large cylinder bushing, mov- 
ing back and forth several times to distribute the oil, and 
removing any excess with a cloth. 

6. Apply the large cover to the emergency portion. 

Q. What lubrication is required for the quick-action 
portion? 



402 



AiPv-Brake Catechism 



A. No parts of the quick-action portion require lubri- 
cation. 

COMMON EXHAUST RESERVOIR. 

Q. Is any part of the control valve ever furnished 
differently than just described? If so, what? 

A. Yes, the three-compartment reservoir. 

Q. In what way is it furnished differently? 

A. There is a type of this reservoir called the '^common 
exhaust'' reservoir which has only one visible exhaust open- 
ing to the atmosphere. 

Q. What is the object of this? 

A. To protect the various exhaust openings from becom- 
ing closed by ice, snow, slush, or sand. 

Q. How is this accomplished? 

A. A common-exhaust chamber is cast around the reser- 
voir into which all the exhaust openings are connected, then 
only one large opening is allowed between this chamber and 
the atmosphere. (See Fig. 146.) 

Q. Is the common exhaust the only openingf between 
the common-exhaust chamber and the atmosphere? 

A. No, there is an opening opposite each regular exhaust 

to permit access to each exhaust separately if desired, but 



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CHAM. EX. 




Fig. 146. Section TiiRoroTT Control Valve Reservoir Having 

Com aj on Exii a u st. 



The 'TC BpwAKE Eqt ipmext 



403 



in ordinan^ service these openings are usually plugged, and 
the common exhaust piped to some protected place. 

Q. In case of piping the common exhaust as just 
mentioned, which pipe-tapped opening should be used? 

A. Any of the one-inch pipe-tapped openings on the 
sides or bottom, as most convenient. 







EMERGENCY 
PISTON EXHAUST 



'^^^^^^^ 



Fig. 147. Control Valve, Common Exhaust Reservoir. Side 

View. 

Q. If no opening is piped away, which one is left 
open? 

A. Usuall}^ several, so that if any one is closed, there 
will still be others through which the exhaust can pass. 

Q. How are the two exhausts on the sides of the 
equalizing portion connected with the others? 

A. By pieces of ^^-inch pipe which connect into the 
common exhaust chamber. (See Figs. 147 and 148.) 

Q. When testing for leakage, how is it possible to 
get at the various exhaust openings? 

A. By removing the ?/^-inch pipes on the sides of the 
equalizing portion, and the plugs from the openings in the 
reservoir opposite to the other exhausts, inserting pipe 
nipples long enough to cause each exhaust to take place 
outside of the reservoir. Then proceed with the tests as 
already outlined. 



404 



Air-Bra KE Catechism 





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The Centrifugal Dirt Collector i05 



THE CENTRIFUGAL DIRT COLLECTOR. 

Q. What is the centrifugal dirt collector? 

A. It is a device to protect valves from dirt, sand, scale 
or any foreign matter carried along through the pipes by 
the flowing air. 

Q. Where is it usually placed? 

A. In the branch pipe from the brake pipe to triple 
valves, control valves or distributing valves. 

Q. Is it used in conjunction with the brake-pipe air 
strainer, usually placed at the point where the branch 
pipe and brake pipe join? 

A. No, the brake -pipe air strainer is omitted when the 
centrifugal dirt collector is used, and a specia' branch-pipe 
tee substituted, which does not have any strainer in it, but 
is so designed as to prevent water in the brake pipe from 
running into the branch pipe. 

Q. At what point in the branch pipe should the cen- 
trifugal dirt collector be installed? 

A. Between the cut-out cock and the triple (or other) 
valve, and as close to the valve as practicable. 

Q. In what position should it be placed? 

A. Vertically with the pipe connections at the top, and 
so the air will flow through it toward the valve in the 
direction marked by the arrow cast on the outside of the 
body. 

Q. How does it operate? (See Pig. 149). 

A. The air entering the device on one side is made to 
rotate around the center, then pass up and out through the 
middle; in so doing, the dirt and foreign matter is thrown 
by centrifugal force against the walls of the conical chamber, 
and thence by gravity falls into the chamber at the bottom, 



406 



Air-Brake Catechism 




Fig. 149. Centrifugal Dirt Collector. 



where the deflector which stands up from the plug at the 
bottom prevents its being drawn up into the outgoing 
stream of air. 

Q. What is the particular advantage of this type of 
air cleaner? 

A. It automatically eliminates the foreign matter with- 
out in any way reducing or restricting the air passage. 

Q. How is the dirt removed from the collector? 

A. By unscrewing the plug at the bottom. 

Q. How often should the dirt collector be cleaned? 
A. Every time the triple (or other) valve is cleaned. 



INDEX 



PAGE 

Adjustment of PC equipment 397 
Air brake and hand brake used 

together 92-94 

Air brake inventions. . . 17, 18, 36 
Air brake, plain automatic. . 18, 19 

Air brake, quick action 19 

Air brake, straight 17 

Air brake, to apply 31 

Air brake, to release 33 

Air brake versus hand brake. . 333 

Air brake, what it is 17 

Air hose 293-298 

Label 294, 295 

Life of hose 294 

Porous hose 294 

Sizes , 293 

Specifications for 295 

Air pumps — see Pumps. 

Air signal system 261-273 

Air strainer 264 

Discharge valve, location . . 261 
Discharge valve, opera- 
tion 262 

Flow of air in 266 

Parts on engine 261 

Parts on car 261 

Reducing valve, location. . 262 
Reducing valve, operation . 263 
Signal valve, location .... 262 
Signal valve, operation . . . 267 
Troubles and cures. . . .269-273 

Whistle, location 265 

American automatic slack ad- 
juster 94, 101 

Application chamber exhaust 

of control valve, location of . . 398 
Application portion of control 

valve 356 

Automatic slack adjuster — see 
Slack Adjuster. 

Auxiliary reservoir 81 

Auxiliary reservoir, how 

charged 28, 45, 68 

Auxiliary reservoir, time to 
charge 33 

Beginnings of the air brake. . 17 
Brake cylinders, PC equip- 
ment 394 

Brake cylinder leakage groove . 80 
Brake cylinder packing ex- 
pander 79 

Brake cylinder pipe choke 

fittings 232 

Brake cylinder piston packing 

leather 79 

Brake cylinder piston travel. . 83 

Brake cylinder pressure 84-87 

Brake cylinder release spring . . 79 
Brake equipment, PC passenger 349 
Brake valves. 

Equalizing reservoir. . .167-170 

Capacity 170 

G-6 brake valve 150-173 



PAGE 

Brake valves — continued. 

Operation 155 

Parts 152 

Positions 154 

Troubles and cures ..170-173 
Use 153 

H-6 automatic brake 
valve 212-221 

S-6 independent brake 
valve 221-228 

Slide valve feed valve. . 162-166 
Adjustment 165 

Operation 163 

Parts 166 

Straight air brake valve . 199 

Brakes fail to apply 45 

Braking power and leverage, 

274-293 

Braking power, car light 
and car loaded 276 

Braking power, general 
rule for calculating 288 

Braking power, high speed 
brake 178, 187 

Braking power, how deter- 
mined 274 

Braking power on driving 
wheel brakes 275. 290 

Braking power on engine 
truck and trailing 
wheels 275 

Braking power on freight 
car 274 

Braking power on pas- 
senger car 275 

Braking power on tenders . 275 

Cylinder pressure, differ- 
ent sizes 277 

Cylinder pressure used in 
figuring braking power. 276 

Cylinder sizes for different 
weights of cars 290 

Hodge system of levers, 

283, 287 

Lever of first class 278 

Lever of second class 279 

Lever of third class 280 

Levers, three classes of . . . 278 

Steven's system of levers . . 287 

Tender brake levers 287 

Broken graduating spring, ef- 
fect of 47 

Cam, brake 292 

Centrifugal dirt collector 405 

Advantage of 406 

Cleaning of 406 

Operation of 405 

Position 405 

Purpose 405 

Check valve in triple valve, 
use of 40 

Choke fittings, brake cylinder 
pipe 233 



407 



408 



Index 



FAGE 

Combined automatic and 
straight air engine and 
tender brake equipment. 193-205 

Double check valve 196 

Handling 197 

Parts of 195 

Purpose of 193 

Straight air brake valve. . 199 

Connections. ., 202 

Location 201 

Operation 202 

Parts 200 

Positions of handle 201 

Troubles and cures 204 

Common exhaust reservoir for 

control valve 402 

Compartment reservoir of con- 
trol valve 355 

Control valve, No. 3-E 355 

Application chamber ex- 

hau.st 398 

Application of gaskets .... 399 

Application portion 350 

Common exhaust reservoir 402 
Emergency cylinder ex- 
haust 399 

Emergency piston exhaust 398 

Emergency position 390 

Emergency portion 356 

Emergency reservoir check 

valve 398 

Emergency slide valve and 

seat 364 

Equalizing portion 355 

Equalizing slide valve and 

seat 362 

Full service position 375 

Graduated release cap. . . . 400 
Graduated release lap 

position 386 

Graduated release positon 384 

Lubrication of 400 

Names of parts 359 

Normal position 365 

Outline 358 

Over-reduction lap posi- 
tion 377 

Over-reduction position. . 377 

Parts of 355 

Port connections 364 

Quick action exhaust 397 

Quick action portion 356 

Reduction limiting 

chamber exhaust 398 

Release and charging posi- 
tion 365 

Release position 381 

Release slide valve and seat 363 
Service brake cylinder ex- 
haust 399 

Service lap position 375 

Service position 372 

Cutting out of PC equipment. 397 
Cut-out cock, main reservoir. . 255 
Cylinder cap, quick-action . 247-250 

Cylinder levers 83 

Cylinder pressure 84 



PAGE 

Cylinder pressure,, emergency 
type "L" triple valve 76 

"Dead" lever 83 

Discharge valve — see Air Sig- 
nal System 

Distributing valve 228-251 

Double check valve 196 

Double pressure control equip- 
ment 189-193 

Advantages of 189 

Benefits of 191 

Object of 189 

Duplex Main- Reservoir Regu- 
lation 174-177 

Benefits of 176 

Connections 174 

Object 174 

ET locomotive brake equip- 
ment 206-260 

Advantages of 208 

Defects of 255-258 

Leaky application cyl- 
inder pipe 255 

Leaky application pi.s- 

ton 257 

Leaky application valve 256 
Leaky distributing-valve 

release pipe 255 

Leaky equalizing slide 

valve 257 

Leaky graduating valve 258 
Leaky rotary valves. . . . 256 

Differences between No. 
5 and No. 6 equip- 
ments 258-260 

Feed valves 25 1-253 

B-6 feed valve 251 

C-6 feed valve 253 

H-6 automatic brake 

valve 212-221 

Comparison with G-6 

valve 215 

Connections 217 

Lubrication 220 

Operation 218 

Parts 217 

Positions of handle 213 

Necessity of 207 

No.6 distributing valve, 228-251 

Automatic release 244 

Connections 228 

Emergency application. 245 

Functions of 229 

Independent application 240 
Independent release .... 242 
Independent release after 
automatic application 246 

Names of parts 234-238 

Service application 243 

Principal parts 208-212 

Pump governor 253-255 

Connections 253 

Operation 254 

Quick action cylinder cap, 

247-250 



Index 



409 



V.\(1,E 

El' locomotive brake equipment 
— continued. 

Operation 249 

Parts 249 

Purpose 247 

When used 248 

Safety valve, use of 250 

Operation 250 

Parts 250 

S-6 independent brake 

valve 221-228 

Connections 222 

Handling 225 

Operation 223, 226 

Parts 221 

Positions of handle 223 

Emergency cylinder exhaust of 

control valve, location ot . . . 399 
Emergency piston exhaust of 

control valve, location of . . . 398 
Emergency piston, triple valve, 

use of ... 40 

Emergency portion of control 

valve 356 

Emergency position of 'control 

valve 390 

Emergency re.servoir check 
valve of control valve, loca- 
tion of 398 

Emergency slide valve and seat 364 
Emergency valve, triple valve, 

use of 40 

Engineer s brake valve — See 

Brake Valves. 
Equalizing piston — see Brake 

Valves. 
Equalizing portion of control 

valve 355 

Equalizing reservoir — see Brake 

Valves. 
Equalizing slide valve and seat . 362 
Expander ring, brake cylinder. 79 

Failure of brakes to apply. . 45 
Feed valve — see Brake Valves 

and ET Equipment. 

First form of air brake 17 

Floating lever 83 

Formulae and rules 344-348 

Freight brake equipments, sizes 

of 83 

Freight equipment 79 

Frozen triple valves 46 

Full service application. 32, 55, 185 
Full service position of control 

valve 375 

Functions of the triple valve in 

the operation of the brake. . 28 

G-6 BRAKE valve 150-173 

Gages, recording 306-309 

Gaskets, application of, to con- 
trol valve 399 

Governors — see Pump Gov 

ernors. 
Graduated release cap of con- 
trol valve, location of 400 



PAGE 

Graduated release lap position 
of control valve 386 

Graduated release position of 
control valve 384 

Graduating spring broken, ef- 
fect of 47 

Graduating stem and spring, 
use of in triple valve 24 

Graduating valve, duty of . . . . 25 

Hand brake, and air brake 

used togetiier 92-94 

Handling of PC equipment . . . 396 

Handling, train 318-341 

High speed brake (old style), 

178-188 
Arrangement on engines. . 181 

Braking power 178, 187 

Cleaning and oiling 187 

Handhng 185 

Length of stops with 188 

Necessity for 178 

Pressures carried 179 

Reducing valve 179 

Hodge lever 83 

Hose — see Air Hose. 

Independent brake valve. 221, 228 

Inspection, train 310-318 

Invention of air brake. .17, 18, 36 

"K" type of triple valve 53 

"L" TYPE of triple valve 64 

Leakage groove, brake cylinder 80 
Leaky valves in triple valve, 

effect of 50 

Leather, piston packing brake 

cylinder 79 

Leverage — see Braking Power 

and Leverage. 
Levers — see Braking Power 

and Leverage. 
Little drum — see Brake Valves. 

"Live" lever vS3 

Lubricants 306 

Lubrication of control valve. . 400 

Main reservoir 146-150 

Capacity recommended. . . 146 

Cooling, pipe 149 

Effects of small reservoir 

capacity 147 

Location 148 

Object of 146 

Water found in 149 

IVIain reservoir cut-out cock. . . 255 

Normal position of control 
valve 365 

OvER-reduction lap position of 
control valve 377 

Over reduction position of con- 
trol valve 377 



■110 



Index 



PAGE 

PC PASSENGER brake equip- 
ment 349 

Adjustment 397 

Cutting out of 397 

Handling: of 396 

How the features are ob- 
tained 351-355 

Names of parts 351 

Necessity of 349 

Novel features of 350 

Use of 349 

Peculiarities and troubles of 
quick-action triple valve .... 44 

"Pipeless" triple valve 67 

Piping 339-343 

Piston, triple valve, duties of . . 24 
Piston, packing leather, brake 

cylinder 79 

Piston travel 83 

Determination of 90 

Effect on train handling, 

87, 88, 89 

Variation in 91 

Plain automatic brake 18 

Plain triple valve 21 

Application position 29 

Emergency position 35 

Lap position 31 

Parts of 22 

Release position 33 

Where used 35 

Port connections of control 

valve 364 

Pressure retaining valves. .101-112 

Connections 102 

Cylinder pressure with. 107-109 

Different sizes Ill, 112 

Double-pressure retainer. 104 

Location 102 

Manipulation 106, 107 

Operation 103 

Positions of handle 102 

Size of small vent part. . 104 

Testing 106 

Troubles with 106 

Use 102 

With what equipments 

used 101 

Pumps 113-138 

Connections 116 

Cross compound pump, 

129-138 

Air valves 134 

Capacity 137 

Intermediate air pres- 
sure 137 

Main valve 134 

Operation 135. 13& 

Size of cylinders 131 

Speed 138 

Steam consumption. ... 130 

Dry pipe 113 

11-inch pump 128, 129 

93'^-inch pump 116-128 

Capacity 119 

Lubrication 120 

Operation 117, 118 



■^ PAGB 

Pumps — Continued. 

Packing. . 119 

Right and left hand. ... 126 

Starting 120 

Troubles and cures. 121-126 

Location 116 

Sizes 113 

Use . . 113 

Pump governors . . i39-145 

Closed drip pipe 141 

Dirty or gummed pin 

valve 142 

Operation 141 

SF-4 pump governor 143 

Quick action automatic brake, 

18, 79 
Quick action cyhnder cap . . 247-250 
Quick action exhaust of control 

valve, location of 397 

Quick action portion of control 

valve 356 

Quick action triple valve 36 

Emergency position 40 

Parts of 41 

Peculiarities and troubles . 44 
Quick action undesired 47 

Recording gages 306-309 

Connections 307 

Speed 30S 

Use 307 

Reducing valve — see Air Signal 
System. 

Reducing valve — see High 
Speed Brake. 

Reduction limiting chamber 
exhaust of control valve, 
location of 398 

Release and charging position 
of control valve 368 

Release position of control 
valve 381 

Release slide valve and seat of 
control valve 363 

Release spring brake cylinder. 79 

Release valve, auxiliary reser- 
voir 81 

Retaining valves — see Pressure 
Retaining Valves. 

Rules and formulae 344-348 

Running piston travel 90.. 99 

Safety valves 192. 250 

Service brake cylinder exhaust 

of control valve, location of . 399 
Service lap position of control 

valve 375 

Service position of control 

valve 372 

Signal system — see Air Signal 

Svstein. 
Signal valve — see Air Signal 

System. 

Slack adjuster 91 . 94-101 

Amount of take up 98 

Cleaning and lubrication. 101 



Index 



411 



PAGE 

Slack adjuster — continued. 

How to apply new shoes. 99 
Length of cylinder lever 

rod 100 

Parts of 96 

Piston travel too short. . . 100 

Piston travel too long. ... 100 

Stuck 101 

Slide valve, triple valve, duties 

of 27 

Slide valve spring, triple valve 28 

Standing piston travel 90, 99 

Strainer, triple valve, use of. 

40, 77 
Straight air brake, why un- 
satisfactory 18 

Straight-air brake valve 199 

Supplementary reservoir 66 

Sweeney compressor 299 

Three-way cock 17, 150 

Triple valve, effect of brake- 
pipe reduction on 29, 69 

Triple valve, "pipeless type" . . 67 

Triple valve, plain . . . '. 21 

Application position 29 

Emergency position 35 

Lap position 31 

Parts of 22 

Release position 33 

Triple valve quick-action 36 

Emergency position 40 

Parts of 41 

Triple valve, type "K" 53 

Emergency position 62 

Lap position . 59 

Parts of 56 

Release position 56 

Retarded release position . 60 

Service position 58 

^izes of 63 



PAGE 

Triple valve, type *'L" 64 

Emergency cylinder pres- 
sure 76 

Emergency position 75 

Full service position 73 

Graduated release position 74 

Quick-service position .... 69 

Release lap position 74 

Release position 73 

Service lap position 71 

Vent valve, duties of 77 

Triple valve, why so called .... 28 
Triple valve, graduating stem 

and spring, use of 24 

Triple valve graduating valve, 

duty of 25 

Triple valve piston, duties of . . 24 
Triple valve slide valve, duties 

of 27 

Triple valve slide valve spring . 28 

Triple valve strainer, use of . . . 40 
Triple valve with leaky valves, 

effect of . . 50 

Triple valves 21 

Triple valves, freezing of 46 

Train handling 318-341 

Train inspection 310-318 

L'NDEsiRED quick action 47 

Vent vaive, type "L" triple 
valve, duties of 77 

Whistle — see Air Signal Sys- 
tem. 

Water brake 299-306 

Compound engines (Bald- 
win) 304 

Simple engines 300 



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11 PRACTICAL II 

11 RAILROAD BOOKS II 



RELATING TO =| 

Air Brakes — Accidents — Boilers — [ § 

Breakdowns — Combustion — Link fl 

Motion — Locomotives — Train Rules, [1 

Walschaert Valve Gears, Etc. jl 

V ■ II 

Published By |1 

THE NORMAN W. HENLEY PUBLISHING CO. || 

132 NASSAU STREET || 

NEW YORK ii 



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A NEW REVISED EDITION. JUST PUBLISHED, 

. . ■ - -i-« — ■ — — ,. ■ - 

UP-TO-DATE 

AIR-BRAKE CATECHISM 

By ROBERT H. BLACKALL 

Pocket Size Prir#» ^2. 00 Fully Illustrated 

384 Pages. Mrri%.c, ^^.uu ^^^^ Colored Plates. 

THIS is the standard book on the Air Brake, written by one of the 
most widely known Air Brake Men in the United States, Canada 
and Mexico. It is a practical and complete study of the air 
brake, including: the E-T Locomotive Brake Equipment, the K (Quick 
Service) Triple Valve for Freight Service, the Type L High-Speed 
Triple Valve, and the Cross Compound Compressor. The operation of 
all parts of the apparatus is explained in detail and a practical way 
of locating their peculiarities and remedying their defects is given. 

If you are preparing for an examination, you should secure a copy 
of this book at once, as it contains over 

2,000 QUESTIONS WITH THEIR ANSWERS 

This is the only book which has been endorsed and used by Air 
Brake Instructors and Examiners on the different roads throughout 
the United States. 

CONTAINING CHAPTERS ON 



I.-BEGINNINGS OF THE AIR BRAKE. 
II.— THE WESTINGHOUSE TRIPLE VALVES. 
IIL—WESTINGHOUSE FREIGHT EQUIPMENT. 
IV.— WESTINGHOUSE AIR PUMPS, 
v.— MAIN RESERVOIR. 

VI.— WESTINGHOUSE OLD-STYLE HIGH-SPEED BR AKT 
VII.— NO. 6 E-T LOCOMOTIVE BRAKE EQUIPMENT. 
VIII.— AIR SIGNAL SYSTEM. 
IX.— BRAKING POWER AND LEVERAGE. 
X.— THE SWEENEY COMPRESSOR. 
XI.— TRAIN INSPECTION. 

XII.— FORMULAE AND RULES FOR AIR BRAKE IN- 
SPECTORS. 



REMEMBER THAT THIS BOOK GIVES FULL AND 

LATEST INFORMATION ON THE OLD AS WELL 

AS THE LATEST AIR BRAKE EQUIPMENT 



JUST PUBLISHED NEW POCKET EDITION 



WESTINGHOUSE E-T AIR BRAKE 
INSTRUaiON POCKET BOOK 

By WM. W. WOOD, Air Brake Instructor 

PRICE $1.50 

CONTAINS examination questions and answers on 
the E-T equipment. Covering what the E-T, 
Brake IS. How it should be OPERATED. What to 
do when DEFECTIVE. Not a question can be asked 
of the ENGINEMAN UP FOR PROMOTION on either 
the No. 5 or the No. 6 E-T equipment that is not 
asked and ANSWERED in the book. If you want to 
thoroughly understand the E-T equipment get a copy 
of this book. It covers every detail. Makes Air Brak« 
troubles and examinations easy. 

AMONG THE CONTENTS OF THIS BOOK ARE: 

The No. 6 E-T Equipment— the Valve— the Pipingr— the Gauges. 
The theory of the Triple Valve, and its principle in application to the 
E-T Locomotive Brake. The Distributing Valve— Colored Charts 
•howinff each and every phase of its action accompanied by Colcred 
Pipinar Diagrams indicating the contained pressures. Theory of the 
Quick- Action Triple Valves, its Importance— its Principle in Appli- 
cation to the Quick- Action Distributing Valve of the No. 6 type. The 
E-6 Safety Valve. The H-6 Automatic Brake Valve— theory and 
principle of the automatically acting brake-pipe pressure Equalizing: 
Discharge Valve— Construction of the H-6 Brake Valve. Trans- 
parency Plates in Color Tints showing the Rotary Valve, and through 
it the Rotary Valve Seat, Ports, etc., in each Operative position of the 
Brake Valve Handle. The S-6 Independent Brake Valve— Its Con- 
Btraction. Transparency Plates similar to those of the H-6 Brake 
Valve, showing the arrangement of Ports in Rotary Valve and Seat 
in each position. The Double-Pressure, B-d Feed Valve. The 
Duplex automatically controlled Excess and Maximum Pressure 
Pump Governor. The C-6 Reducing Valve. The "Dead Engine 
Feature** of the No. 6 E-T Equipment. Combined Air Strainer and 
Check Valve— its application to the Train Air Signal System. 

Operation of the No. 6 E-T Locomotive Brake— Freight Service- 
Passenger Service— Switching Service— General Braking Service- 
Grade Work, etc. Reporting Work on the No. 6 Equipment. Testine: 
the Equipment. Leaking or Broken Pipes of No. 6 Equipment. 

The No. 5 E-T Locomotive Brake Equipment— Its distinctive 
features as compared with the No. 6 T3rpe— Its Operation— Leaking 
or Broken Pipes in the No. 5 Equipment. 

Filled with Colored PUtei - Skowing Tarious Pressures 



REVISED POCKET EDITION 



LOCOMOTIVE BREAKDOWNS 

AND THEIR REMEDIES 

By GEO. L FOWLER, revised by WM W. WOOD. Air Brake Instructor 
270 Pages PRICE $1.00 Fully Illustrated 

ENGINEERS are paid nowadays for getting their 
engines into the terminal on time, and to accom- 
plish this there must be no casualties EN ROUTE that 
will cause delay ; accidents, however, will happen, and 
it is the knowledge of HOW TO AVOID DELAY IN 
CASE OF ACCIDENTS that the Company requires of 
engineers nowadays, and what to do in case of break- 
downs. The revised pocket edition of "Locomotive 
Brakedowns ' ' is absolutely necessary to every engineer, 
fireman, and shop man, because it treats of every 
possible engine trouble, and presents the remedy, in 
the form of questions and answers. Just imagine all 
the common troubles that an engineer may expect to 
happen sometime, andithen add all of the unexpected 
ones, troubles that could occur, but that you had never 
thought about, and you will find that they are all here, 
in this Up-to-Date Edition of * 'Breakdowns, "with^tho 
very best methods of repair. 

CONTENTS 



I.~Defective Valves; II.— Accidents to the V&lve Motion; 
ni.— Accidents to Cylinders, Steam Chests, Cylinders and Pistons; 
IV.— Accidents to Guides, Crossheads and Rods ; V, -TheWalschaert 
Valve Motion ; The Baker- Pi llord Improved Valve Gear ; Accidents 
that May Happen to these Gears ; VI.— Accidents to Running Gears ; 
Vn.— Truck and Frame Accidents ; VIII.- Boiler Troubles ; IX.— 
Defective Throttle and Steam Connections; X.— Defective Draft 
Appliances; XI.— Pump and In jector Troubles ; XII.— Accidents to 
Cab Fixtures; XIII.— Tender Accidents; XIV.— Miscellaneous 
Accidents: XV.— Compound Locomotive Accidents; XVI. — Tools 
a«rd Appliances for Making Engine Repairs ; XVII.— Air Brake 
Troubles ;-XVm.— The Pyle-National Electric Headlight. 



JUST PUBLISHED 
THIRD EDITION, REVISED AND ENLARGED 

THE WAISGHAERT and OTHER MODERN 
RUIAL VALVE GEARS FOR LOCOMOTIVES 

By WM. W. WOOD, Air Brake Inspector 

245 Pages PRICE, $1.50 fiSusTRATED 

WITH the adoption of the Walschaert Valve Gear 
on nearly every modem locomotive in America, 
this book fills a place of real interest and usefulness. 
By a careful study of its pages, one can THOROUGHLY 
Understand the Walschaert Valve Gear, as the author 
takes the plainest form of a steam engine — a stationary 
engine— in the rough, that will only turn its crank in 
one direction— and from it builds up — with the reader's 
help, a modern locomotive equipped with the Wal- 
schaert Valve Gear, complete. 

THE CONTENTS OF THE BOOK ARE DIVIDED INTO FIVE PARTS 

THE FIRST DIVISION contains an analysis of the Walschaert 
Valve Gear. 

THE SECOND DIVISION treats on the Designinfi: and Erecting of 
the Valve Gear. 

THE THIRD DIVISION has to do with the actual work of the Wal- 
schaert Valve Gear on the Road. ^ 

THE FOURTH DIVISION is composed entirely of questions and 
answers on the Walschaert Valve Gear. 

THE RFTH DIVISION deals with the Setting of Valves with the 
Walschaert Gear, the Hobart- Allf ree Valve and Valve Gear, and 
the Baker-Pilloid Valve Grear in its original and improved form. 

The book is fully fllustrated, and a novel and inter- 
esting feature of the book is tire folding diagrams with 
cardboard valve models, by means of which the actual 
operation of the valve under the influence of the Wal- 
schaert motion can be studied. 



NEW EDITION JUST PUBLISHED 

LOCOMOTIVE CATECHISM 

By ROBERT GRIMSHAW, M. E. 
d25 Pages 437 Illustrations and Three Foi^ag PUtea 

PRICE $2.50 

THIS book commends itself an once to every EIngineer 
and Fireman, and to all who are going in for 
examination, or promotion. 

In plain language, with full, complete answeri, 
not only all the questions asked by the examining 
engineer are given, but those which the young and less 
experienced would ask the veteran, and which old 
hands ask as "stickers." 

It is a veritable Encyclopasdia of the Locomotive, 
is entirely free from mathematics, and thoroughly up-to- 
date. St«dy it and you will know year engine thoroughly* 

CONTAINS OVER 4000 EXAMINATION QUESTIONS 
WITH THEIR ANSWERS. 

AMONG SOME OF THE SUBJECTS TREATED ARE; 

Accidents and Emererencies ; Air-Brakes; Alfree-Hubbell 
Gear ; Allen Gear ; Automatic Reducing: Valve ; Automatic Slack 
Adjuster; Auxiliary Reservoir; Blower; Boilers; Brake Cylin- 
der; Cab; Check Valve; Collisions; Combustion; Compound 
Locomotives; Crosshead and Guides; Cut-off and Expansion; 
Cylinder; Derailment; Eccentric Motion ; Eccentric Rods ; Elec- 
tric Headligrht ; Engrine and Tender Brakes ; Ensineman's Tender 
Valve; Equalizing: Bars; Examination of Firemen; Firing; 
Firing: with Oil ; Four-Cylinder Compounds ; Gears ; Gooch G^r ; 
Headlig:ht ; Indicator : Injector ; Joy Gear ; K Tripple Valve ; 
Knocks and Pounds; Lubrication; Piston Valves; "Quick- 
Action" Brake : Relief Valves: Richmond-Mell in Compound ; Slide 
Valve ; Slide- Valve Feed Valve ; Superheated Steam ; Sweeney 
Compressor ; Tandem Compounds; Three-Cylinder Compounds; 
Vacuum Brake; Valve defers; Valve Motion Models; Valve 
Betting:; Walschaert Gear ; Yoons Valyc Gear. 



JUST PUBLISHED! 

PRACTICAL INSTRUCTOR 
AND REFERENCE BOOK for 

LOCOMOTIVE FIREMEN AND ENGINEERS 

B J CHARLES F. LOCKHART 
368 Pages. PRICE, $1.50 88 Illustrations. 

THIS book treats in a thorough manner of the 
rail road man's duties and how to properly per- 
form them. It also contains practical information on : 
The Construction and Operation of Locomotives; 
Breakdowns and Their Remedies; Air Brakes an<i Valve 
Gears. Rules and Signals are handled in a thorough 
manner. As a book of reference it cannot be excelled. 
An entirely new book on the Locomotive. It 
appeals to every rail road man, as it tells him how 
things are done and the right way to do them. Written 
by a man who has had years of practical experience 
in locomotive shops and on the road firing and running. 
The information given in this book cannot be f oimd in 
any other similar treatise. Eight hundred and fifty-one 
questions with their answers are included which will 
prove specially helpful to those preparing for ex- 
amination. 

THE BOOK IS DIVIDED INTO SIX PARTS, AS FOLLOWS; 

Part I.— TH£ FIB£MAN'3 DUTIi:S. 

Part II.— GENBBAIi DESCRIPTION of the I.0C01II0TIYB. 

Part III.— BREAKDOWNS AND THEIR REMEDIES^ 

Part IT.-AIR BRAELES. 

Part v.— EXTRACTS FROM STANDARD RULES^ 

P»r^ TI.~QUESTION8 FOB EXAMINATION^ 



JUST OFF THE PRESS. POCKET EDITION. 



TRAIN RULE EXAMINATIONS 
MADE EASY 

By a E. COLLINGWOOD 

S56Pafire8— Fully Illastrated DDTtf^C #t OC 

with Train Signals in colors a I\1\^IL ^ i .^O 

THIS is a book which every railroad man, no matter 
what department he is in, should have, as it is 
written by a man who understands the subject thor- 
oughly. Mr. G. E. Collingwood, the author, is a 
recognized authority on train rules and train orders. 
For years he has edited the train rule department in 
four of the foremost railroad magazines in the United 
States. If you want to thoroughly understand the 
subject get a copy of this book, as every detail is 
covered, and puzzling points are explained in simple, 
comprehensive language. This book is the only 
practical work on train rules in print. 

Contains complete and reliable information of the 
Standard Code of Train Rules for single track. Shows 
Signals in Colors, as used on the different roads. 
Explains fully the practical application of train orders, 
giving a clear and definite underslandifig of all orders 
which may be used. The meaning and necessity for 
certain rules is explained in such a manner that the 
student may know beyond a doubt the rights conferred 
under any orders he may receive or the action required 
by certain rules- 

Nearly 500 Questions with their Answers are Included 

AMONG THE SUBJECTS TREATED ARE 

The American Railway Association ; Standard Time ; Dividing 
points between the Time Sections; Personal Admonition; Defin- 
itions of Terms used; Time-Tables; Signals; Use of Signals; 
Superiority of Trains ; Movement of Trains ; Train Orders ; Forms 
of Orders; Combinations of Orders; Clearance Cards; Train 
Identification; Examination Questions; Answers to Examination 
Questions; Standard Code of Train Rules for Siufirle Track: 
of Hand, Flas: and Lamp Sisi^als in Colors, ate. 



JUST PUBLISHED 

Diary of a 
Round House Foreman 

By T. S. REILLY 

Late Associate Editor "Railway Review." 

176 PAGES PRICE $1.00 

T^HIS is the Greatest Book of Railroad Experiences 
* ever published. Containing a fund of information 
and suggestions along the line of handling men, organ- 
izing, etc., that one cannot afford to miss. Railroad 
men in any capacity will thoroughly enjoy and appreci- 
ate the valuable hints and funny experiences contained 
between the covers of this book. It will at once find 
a permanent place in the library of all who want to get 
ahead, as well as those who have climbed the ladder 
and enjoy looking back to the characters and times 
found only on a railroad. 

New stories and laughable experiences are told, as can only bo 
done, by one filled with the sense of Irish humor and the power of 
imparting: in writing: the humorous incidents connected with the 
knotty problems involved in every day life of a round-house foreman. 

While most of the sufi:gestions are specifically connected with the 
duties of a round-house foreman, many of the stories are, in reality, 
part of Mr. Reilly's life, obtained while holding positions of Machin- 
ist, Round -House Foreman, Fireman, Engineer, Master Mechanic 
and Superintendent of Motive Power. 

These articles first appeared serially in the "Railway Review** 
and are now put in book form, on account of the continued requests 
from readers for them. The author, a jolly fellow liked by all, had 
the faculty of seeini: a thread of fun in the most serious of complica- 
tions. 

An Interesting Book for Every Railroad Man to 
Read and Profit By. 



A CATECHISM ON THE 

COMBUSTION OF COAL 

AND THE PREVENTION OF SMOKE 

By WILLIAM M. BARR., M. E. 

Nearly 350 Pages PRICE $1.00 Fully Illustrated 

A PRACTICAL TREATISE FOR 
Ensineers. Firemca and all others interested in Fael EeoBomy*. 

TO be a success a fireman roust be " JAght on Coal." He mast 
keep his fire in grood condition, and prevent, as far as possible, 
the smoke nuisance. To do this, he should know how coal burnt, 
bow smoke is formed and the proper burning of fuel to obtain the 
best results. He can learn this, and more too, from Barr's 
••COMBUSTION OF COAL AND THE PREVENTION OF 
SMOKE/* It is an absolute authority. 

Contains nearly 500 questions with their answers^ 
giving the needed information to enable anyone to pass 
any examination on combustion* 

AMONG THE SUBJECTS TREATED ARE 

Locomotive Furnace Details. Limitations of Locomotive Fire* 
Box. Advantafires of large Grate Area. Rate of Combustion in 
Locomotive Boilers. Function of Fire- Brick Arch in Locomotive 
Fire-Boxes. Usual Construction of Brick Arch in Locomotive Fire- 
Boxes. Does the Brick Arch in Locomotive Fire-Boxes cause leaky 
Flues? Tubular Water Grates. Stationary Coal Burning Grate. 
Shaking Grate. Comparison of Evaporated Power of Anthracite and 
Bituminuous Coal in Locomotive Practice. Practical results of single 
shovel Firing on the B. C. R. and N. Ry. Saving in Coal by light 
Firing in Locomotives. The best Method of Firing a Locomotive. 
Noticeable improvements in Connection with light Firing and Boiler 
Repairs. Direct saving upon the Brick Arches in Locomotive Fire- 
Boxes by Light Firing. Advantages attained by the lateral exten- 
sion of Locomotive Fire-Boxes. Disadvantages of a wide Fire-Box 
in Locomotives. Division of wide Fire-Box in Locomotives into two 
separate Furnaces. Evaporative results in ordinary Locomotive 
Practice. Most efficient form of Exhaust Tip. Size of average 
Exhaust Tips. Conclusions reached regarding means for increase 
in Production of Steam by Increased Draft. Strong's Locomotive 
Fire-Box. How the Smokeless Combustion of Bituminuous Coal is 
carried out in Pratice in Locomotives. Details of front ends of Loco- 
motives Sa Pac. Ry. Furnace Door Details. Details of Shaking 
Grate. Details of Ash Pan. Facts given in daily report of Traveling 
Firemen So. Pac. Ry. 

Hydrocarbon Oil as a Fuel for Locomotives, Heating Power of 
Crude Petroleum. Success attending the use of Liquid Fuel as 
Auxiliary to Coal for Locomotive Engines. Changes necessary to 
Convert a Coal into an Oil-Burning Locomotive. Construction of 
Atomizers for Burning Oil on So. Cal. Railroad. How Oil is supplied 
to Burner under Pressure. Size of Exhaust nozzle when burning 
OiL Are Oil Fires Smokeless? Effect of Products of Combustion of 
an Oil Fire upon the Tubes of a Boiler. Relative cost of Oil and 
Coal as a Fuel in Locomotive Practice. 



JUST ISSUED NEW REVISED EDITION 



Locomotive 
Boiler Construction 

By FRANK A. KLEINHANS 

478 Pages PRICE, $3.00 Five Folding 

350 Illustrations * axav^*-> v*^.vvr pj^^^^ 

THIS IS ONE OF THE BEST BOOKS OF ITS KIND EVER 
PUBLISHED. IT TAKES THE READER FROM THE 
LAYINc; OUT OF THE SHEETS TO THE COMPLET- 
ED BOILER. THERE ISNT A MAN WHO HAS ANY- 
THING TO DO WITH BOILER WORK, EITHER NEW 
OR REPAIR WORK, WHO DOESN'T NEED THIS BOOK. 
THE MANUFACTURER, SUPERINTENDENT, FORE- 
MAN, AND BOILER WORKER— ALL NEED IT. NO 
MATTER WHAT THE TYPE OF BOILER, YOU'LL 
FIND A MINT OF INFORMATION THAT YOU 
WOULDN'T BE WITHOUT. 

THIS book takes the locomotive boiler up in the order in 
which its various parts go through the shop. Each 
step, from the first mark on the sheet to the finished boiler, 
receives careful attention in a thoroughly practical way, 
shows all types of boilers used ; gives details of construct- 
ion ; practical facts, such as life of riveting, punches and 
dies ; work done per day, allowance for bending and flanging 
sheets, and other data. Including the recent Locomotive 
Boiler Inspection Laws and Examination Questions with 
their answers for Government Inspectors. 

CONTENTS 



Laying Out Work— Flanging and Forging, Punching, 
Shearing and Plate Planning— Bending— Macliining 
Parts— Boiler Details— Assembling and Calking, Fin- 
ishing Parts, Boiler Shop Machinery— General Tables- 
Plates Sho^ving Types of Modern Locomotive Boilers- 
Locomotive Boiler Inspection— Questions and Answers 
on Boiler Inspection. 



LINK MOTIONS. VALVES AND 
VALVE SETTING 

By FRED H. COLVIN 
FULLY ILLUSTRATED PRICE, SOc. 

A HANDY book for the engineer or machinist that 
clears up the mysteries of valve setting. Shows 
the different valve gears in use, how they work, and 
why. Piston and side valves of different types are 
illustrated and explained. A book that every rail road 
man in the motive power department ought to have. 

CONTAINS CHAPTERS ON 



Locomotive Link Motion.— Direct and Indirect Mo- 
tion ; lap ; lead ; crossed rods, etc. 

Valve Movements.— Twelve charts showing com- 
plete movements of valves under various conditions of 
travel ; lap and lead. 

Setting Slide Valve.— Finding dead centers ; increas- 
ing or decreasing leads ; changing length of eccentric 
rods or blades ; moving eccentrics on axle. 

Analysis by Diagrams.— Illustrates the various con- 
ditions that occur with direct or indirect motion ; inside 
and outside admission and different methods of connect- 
ing the link. New facts and rules in connection with 
link motions and valve setting. 

Modem Practice. — Shows what is being done in the 
matter of eccentric rod lengt? s ; angularity of eccentric 
rods; leads; proportions of travel; eccentric throw; 
lap; ports; piston speed, etc. 

Slip of Block.— Illustrates how and why '*Slip" ex- 
ists and how it is hardly considered in modern practice. 

Slide Valves. — Shows balanced D Valve, Allen Valve 
and Wilson's American Valve. 

Piston Valves.— Shows eight varieties of piston 
valves; two styles of valve bushings or cages and device 
for getting water out of cylinder. Gives experience of 
several roads with piston valves. 

Setting Piston Valves.— Plain directions on points 
differing from slide valves. 

Other Valve Geari.— Joy- Allen, Walschaert, Gooch, 
<llfull-Hubbell, etc. 



SIXTH EDITION JUST PUBU SHED 

MACHINE SHOP ARITHMETIC 

By COLVIN- CHENEY 

145 Pages Price^ SOc. Bound in Cloth 

THIS is an arithmetic of the things you have to do 
with daily. It tells you plainly about : how to 
find areas of figures — how to find surface or 
volume of balls or spheres — handy ways for calcula- 
ting — about compound gearing — cutting screw threads 
on any Ilathe — drilling for taps — speeds of drills, 
taps, emery wheels, grindstones, milling cutters, etc. 
— all about the Metric system with conversion tables— 
properties of metals — strength of bolts and nuts-^ 
decimal equivalent of an inch. All sorts of machine 
shop figuring and 1001 other things, any one of which 
ought to be worth more than the price of this book to 
you, as it saves you the trouble of bothering the 
boss. 



This is one of the most popular Mechanical books 
in print. It contains the greatest half a dollar's worth of 
information ever put between the two covers of a book. 
Treats on everything relating to Machine Shop figuring. 



JUST PUBLISHED. 



Prevention of Railroad Accident 



OR 

Safety in Railroading 

By GEORGE BRADSHAW 
POCKET SIZE p-:^^ en#. fully 

192 PAGES I^nCe, OUC« ILLUSTRATED 

A HEART-TO-HEART talk with Railroad Employes, 
dealing with facts, not theories, and showing the 
men in the ranks, from e very-day experience, how 
accidents occur and how they may be avoided. The 
book is illustrated with seventy original photographs 
and drawings showing the safe and unsafe methods of 
work. No visionary schemes, no ideal pictures. Just 
plain facts and Practical Suggestions are given. Every 
railroad employe who reads the books is a better and 
safer man to have in railroad service. It gives just 
the information which will be the means of preventing 
many injuries and deaths. 

The author of this work is employed by the N. Y. C. & H. R. RR. 
in special service for the prevention of accidents. For many years he 
has been constantly engaged in the study of railroad accidents, and 
from the mass of facts, obtained by years of study, he has formed 
certain conclusions as to the prevention of accidents. 

One of these conclusions is that the majority of preventable acci- 
dents are due, not to defective material or improper method, but to 
the men themselves. While considerations of safety still call for 
much improvement in physical conditions, it is a fact that in no field 
of activity has there been greater material advancement than in rail- 
roadingr. Yet the record of injury to employes has been growinfir 
worse every year. 

This work takes up the human element in a heart-to-heart talk 
with employes. It show them (1) the seriousness of the personal in- 
jury problem and that they are the real sufferers from present condi- 
tions ; and (2) how they themselves are responsible for the personal 
injury record and how they can improve it. 



All Railroad Employes should procure a copy, read it» 
and do their part in preventing accidents. 



THE APPUCATION OF HIGHLY 

SUPERHEATED STEAM TO L0C9M0TIVES 

By ROBERT GARBE 

Editad by LESLIE S. ROBERTSON 

Very fully Illustrated with Folding Plates and Tables 
PRICE, $2.S0 

A PRACTICAL work specially prepared for the use 
of all interested in the application of superheated 
steam to locomotives, written by a man who probably 
has had greater experience and is more thoroughly 
familar, in a practical way, with superheated steam in 
locomotive practice than any other man on either conti- 
ent. While the book deals with highly superheated 
steam, the matter of low superheat is thoroughly dis- 
cussed. In addition to the theoretical discussion of the 
subject the book also contains full illustrated descrip- 
tions, with a discussion of the merits, of all the better 
known superheaters in the world. The details of the 
locomotive, outside of the superheater, for satisfactorily 
using steam at this high temperature are discussed and 
the designs introduced by Herr Garbe are illustrated. 
Reports on a number of very complete and practical 
tests form the concluding chapter of the work. This 
book cannot be recommended too highly to those motive 
power men who are anxious to maintain the highest 
efficiency in their locomotives. 

CONTAINS CHAPTERS ON 



I.-GENERATION OP HIGHLT SUPERHEATED STEAM. 

II.-SUPERHEATED STEAM AND THE TWO-CYLINDER 
SIMPLE ENGINE. 

III.-COMPOUNDING AND SUPERHEATING. 
IV.— DESIGNS OF liOCOMOTIVE SUPERHEATERS. 
T.-DESIGNS OF LOCOMOTIVE SUPERHEATERS.-cont*d 
VI.~CONSTRUCTIVE DETAILS OF LOCOMOTIVES US- 
ING HIGHLY SUPERHEATED STEAM. 

Til.— EXPERIMENTAL AND WORKING RESULTS WITH 
SUPERHEATED STEAM LOCOMOTIVES. 



AMERICAN COMPOUND LOCOMOTIVES 

By FRED H. COLVIN 
142 Pages PRICE, $1.00 Fully Illustrated 

A BOOK showing every type and make of Compound 
Locomotives in use in the country. Tells in plain 
English — How to Handle Them. How to Repair Them. 
What to do if They Break Down. How to Disconnect 
Them. How to Set Valves. How to Test for Leaks 
and Locate Blows. All about Piston Valves. Reduc- 
ing Valves. Valve Motion. Lubricating, etc. 

CONTAINS CHAPTERS AS FOLLOWS : 



A Bit of History. Theory of Compoundinfir Steam Cylinders. 
Baldwin Two-Cylinder Compound. Pittsburg: Two-Cylinder Com- 
pound. Rhode Island Compound. Richmond Compound. Rogrers 
Compound. Schenectady Two-Cylinder Compound. Vauclain Com- 
pound. Tandem Compounds. Baldwin Tandem. The Colvin- Wight- 
man Tandem. Schenectady Tandem. Balanced Locomotives. Bald- 
win Balanced Compound. Plane for Balancinar. Locatinsr Blows. 
Breakdowns. Reducing Valves. Drifting. Valve Motion. Discon- 
necting. Power of Compound Locomotives. Practical Notes. 



CHARTS 

TRACTIVE POWER CHART 

A chart whereby you can find the tractive power or 
drawbar pull of any locomotive, without making a 
figure. Shows what cylinders are equal, how driv- 
ing wheels and steam pressure affect the power. 
What sized engine you need to exert a given draw- 
bar pull or anything you desire in this line. Price, 50c. 

PASSENGER CAR CHART 

A chart showing the anatomy of a passenger car, 
having every part of the car numbered and its 
proper name given in a reference list. Price, 20c. 

BOX CAR CHART 

A chart showing the anatomy of a box car, having: 
every part of the car numbered and its proper name 
given in a reference list. Price, 20c. 

GONDOLA CAR CHART 

A chart showing the anatomy of a gondola car, hav- 
ing every part of the car numbered and its proper 
reference name given in a reference list. Price, 20c 



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